Significant Increase In Internal Rotation Research Articles

Management of Massive Rotator Cuff Tears: Prospective study in 218 patients

BackgroundNo consensus exists about the management of massive and symptomatic rotator cuff tears (RCTs). The objective of this study was to compare the 12-month clinical outcomes of various treatment options for massive RCTs. HypothesisArthroscopic surgery has a role to play in the treatment of massive and apparently irreparable RCTs. Material and methodsA prospective multicentre non-randomised study was performed in patients with massive RCTs managed non-operatively (NONOP) or by arthroscopic tenotomy/tenodesis of the long head of biceps (aTLB), arthroscopic partial tendon repair (aPTR), arthroscopic latissimus dorsi transfer (aLDT), or reverse shoulder arthroplasty (RSA). Clinical outcomes were evaluated based on the Constant score, Subjective Shoulder Value (SSV), and American Shoulder and Elbow Surgeons (ASES) score after 3, 6, and 12 months. ResultsThe 218 included patients (mean age, 69 years) were distributed as follows: NONOP, n=71; aTLB, n=26; aPTR, n=61; aLDT, n=25; and RSA, n=35. After 12 months, the mean Constant score, SSV, and ASES score values were 70, 68%, and 73, respectively, and had improved significantly versus the preoperative values in all treatment groups. RSA was the only treatment followed by improvements in all Constant score items. Active forwards elevation improved significantly in the NONOP (+25°), aPTR (+26°), and RSA (+66°) groups. An improvement in active external rotation was seen only in the RSA group, where it was small (+10°, p=0.046). Significant increases in internal rotation were seen in the NONOP (+1.6 points) and aPTR (+1.7 points) groups. ConclusionArthroscopic techniques (aTLB, aPTR, and aLDT) for managing massive irreparable RCTs produce significant functional gains. Partial tendon repair (aPTR) and RSA may provide better outcomes than isolated aTLB or aLDT. Level of evidenceIII, non-randomised prospective study.

A biomechanical analysis of triangular medial knee reconstruction

BackgroundThe purpose of this study was to evaluate and compare knee kinematics and stability following either triangular or anatomical reconstruction of the superficial medial collateral ligament (sMCL) and posterior oblique ligament (POL).MethodsIn a cadaveric model (12 knees), the stability and kinematics following two experimental sMCL and POL reconstructions were compared in sMCL- and POL-deficient knees versus normal knees. The first reconstruction was a triangular reconstruction of the sMCL and POL, while the second involved an anatomical reconstruction of the sMCL and POL. All knees were tested through four different states. The changes in valgus angles, external rotation, and internal rotation were measured in the normal and sMCL- and POL-deficient knees, as well as in the knees that had undergone the two different forms (triangular and anatomical) of reconstruction.ResultsAfter initial sectioning of the sMCL and POL, we observed significantly increased valgus rotation, external rotation, and internal rotation at all knee flexion angles (0°, 20°, 30°, 60°, 90°). Additionally, passive stability testing demonstrated a significant increase in tibial internal rotation following triangular reconstruction compared with anatomical reconstruction at knee flexion angles of 20° and 30°. A significant increase in internal rotation was present following triangular reconstruction compared with anatomical reconstruction at 20° (mean difference = 2.77) (P = 0.008) and 30° (mean difference = 0.99) (P < 0.001) of knee flexion.ConclusionThis study suggests that anatomical sMCL and POL reconstruction produces slightly better biomechanical stability than triangular reconstruction. However, triangular reconstruction may restore a near-normal knee joint is both less invasive and more practical.

Biomechanical Evaluation of Pediatric Anterior Cruciate Ligament (ACL) Reconstruction Techniques With and Without the Anterolateral Ligament (ALL).

Two popular physeal-sparing procedures used in the management of anterior cruciate ligament (ACL) injuries in skeletally immature patients are the iliotibial band (ITB) ACL reconstruction (ACLR) and the all-epiphyseal (AE) ACLR. Although there has been concern for overconstraint of the lateral compartment of the knee with the ITB ACLR technique, rotational stability, as provided by the anterolateral ligament (ALL) and ACL, has not been assessed in the setting of pediatric ACLR techniques. Our hypothesis is that the ITB ACLR and AE ACLR with ALL reconstruction (ALLR) will best replicate the biomechanical profile of the intact ACL that is lost with transection of the ACL and ALL. Eight cadaveric legs were statically loaded with an anterior drawer force and varus, valgus, internal and external rotational moments at 0, 30, 60, and 90 degrees of flexion. Displacement and rotation were recorded in the following conditions: intact ACL/intact ALL, ACL-deficient/intact ALL, ITB ACLR/intact ALL, ITB ACLR/ALL-deficient, ACL-deficient/ALL-deficient, AE ACLR/ALL-deficient, AE ACLR/ALLR. Both ACLR techniques reduced anterior tibial translation from the ACL-deficient state, but neither restored it to the intact state (P<0.05), except in full extension. ALL deficiency increased anterior tibial translation in the ACL-deficient state (P<0.05). In rotational testing, no significant increase was seen with transection of the ACL, but the ACL-deficient/ALL-deficient state had a significant increase in internal rotation (P<0.05). This was significantly restored to the intact state at most flexion angles with the ITB ACLR without rotational overconstraint of the lateral compartment. The AE ACLR/ALL-deficient state and AE ACLR/ALLR improved rotational stability at lower flexion angles, but not at 60 and 90 degrees. There were no significant changes in varus/valgus moments. In this model, the ITB ACLR provided the superior biomechanical profile between our tested reconstructions. It best corrected both AP and rotatory stability without overconstraining the knee. The AE ACLR and AE ACLR/ALLR improved both parameters but not at all flexion angles and not as robustly. ACL deficiency in the knee increased anterior tibial translation, but did not affect rotatory stability. ALL deficiency in the knee increased anterior displacement and rotational moments in the ACL-deficient state. Cadaveric Laboratory Study. The ITB ACLR seems to be the biomechanically superior pediatric ACLR technique to regain translational and rotational stability.

The Lateral Meniscus Posterior Root and Meniscofemoral Ligaments are Stabilizing Structures in the ACL Deficient Knee: A Biomechanical Study

The lateral meniscus posterior root was a significant primary stabilizer of the knee for internal rotation and anterior tibial translation during pivoting activities at lower flexion angles and internal rotation at higher flexion angles. The menisci have an important role in stabilizing the knee joint. The biomechanical effects of lateral meniscal posterior root tears with versus without meniscofemoral ligament (MFL) tears in anterior cruciate ligament (ACL) deficient knees have not been studied in detail. To determine the biomechanical effects of the lateral meniscus (LM) posterior root tear in anterior cruciate (ACL) - intact and ACL-deficient knees. In addition, the biomechanical effects of disrupting the meniscofemoral ligaments (MFLs) in ACL deficient knees with meniscal root tears was evaluated. It was hypothesized that disruption of the posterior horn lateral meniscal root attachment would cause a significant increase in internal rotation during simulated pivot shift and internal rotation tests in the ACL-deficient knee, both with and without intact meniscofemoral ligaments. In addition, it was hypothesized that disruption of the LM root and MFLs would significantly increase internal rotation at high flexion angles. Controlled laboratory study. Ten paired (n = 20) fresh-frozen cadaveric knees were mounted in a 6 degree-of-freedom robot for testing and divided into two sequential cutting groups. The sectioning order for group 1 was (1) ACL, (2) LM posterior root, (3) MFLs, and for group 2 was (1) LM posterior root, (2) ACL, and (3) MFLs. For each cutting state, displacements and rotations of the tibia were measured and compared to the intact state following a simulated pivot shift test (5 Nm internal rotation torque combined with a 10 Nm valgus torque) at 0°, 20°, 30°, 60° and 90° of knee flexion; an anterior translation load (88 N) at 0°, 30°, 60° and 90° of knee flexion; and internal rotation (5-Nm) at 0°, 30°, 60°, 75° and 90° of knee flexion. Cutting the LM root and MFLs significantly increased ATT during a simulated pivot shift test at 20° and 30° when compared to the ACL cut state (both p<0.05). Cutting the LM root in ACL intact knees significantly increased internal rotation by between 0.7° ± 0.3° and 1.3° ± 0.9° (all p<0.05), except at 0° (p=0.136). When the ACL + LM root cut state was compared to the ACL cut state, the increase in internal rotation was significant at higher flexion angles of 75° and 90° (both p<0.05) but not between 0°- 60° (all p>0.2). For an anterior translation load, cutting the LM root in ACL deficient knees significantly increased ATT only at 30° (p=0.007). The LM posterior root was a significant stabilizer of the knee for anterior tibial translation during a simulated pivot shift test at lower flexion angles, and internal rotation at higher flexion angles. Increased knee instability due to lateral meniscal root deficiency may contribute to increased functional limitations in patients and potentially to increased loads on ACL reconstruction grafts.

Biomechanical Evaluation of Pediatric Anterior Cruciate Ligament Reconstruction Techniques with and without the Anterolateral Ligament

Objectives:Management of anterior cruciate ligament (ACL) injuries in skeletally immature patients is controversial and several surgical procedures have been developed. The two most popular physeal sparing procedures are the iliotibial band (ITB) ACL reconstruction (ACLR) and the all-epiphyseal (AE) ACLR. There has been some concern for over-constraint of the knee with the ITB ACLR while the AE ACLR is technically challenging and can still risk growth disturbance. There has been interest recently into the anterolateral ligament (ALL) and its role in rotational stability, but it has not been assessed in the setting of pediatric ACLR techniques. The ITB ACLR includes a lateral tenodesis of the IT band to the femur that closely approximates the ALL. Our hypothesis is that the ITB ACLR and AE ACLR with ALL reconstruction (ALLR) will best replicate the biomechanics profile of the intact ACL.Methods:Eight cadaveric legs were statically loaded with an anterior drawer force and varus, valgus, internal and external rotational moments at 0°, 30°, 60°, and 90° of flexion. Displacement and rotation was recorded in the following conditions: intact ACL/intact ALL, ACL deficient/intact ALL, ITB ACLR/intact ALL, ITB ACLR/ALL deficient, ACL deficient/ALL deficient, AE ACLR/ALL deficient, AE ACLR/ALLR.Results:Both ACLR techniques reduced anterior translation from the ACL deficient state but neither restored translation to the intact state (p<0.05) except in full extension. ALL deficiency increased anterior translation in the ACL deficient state (p<0.05). In rotational testing, only the ACL deficient/ALL deficient state had a significant increase in internal rotation (p<0.05). This was significantly restored at all flexion angles with the ITB ACLR. There was no rotational over-constraint in any flexion angle with the ITB ACLR. The AE ACLR/ALL deficient state and AE ACLR/ALLR improved rotational stability at lower flexion angles, but not at 60° and 90°. There were no significant changes in varus/valgus moments.Conclusion:In this model, the ITB ACLR best corrected both parameters at all angles without over-constraining the knee and without the need for an ALLR. The AE ACLR and AE ACLR/ALLR improved both parameters but not at all flexion angles. The ITB ACLR appears to be the simpler pediatric ACLR technique to regain translational and rotational stability. ALL deficiency in the knee increased anterior displacement and rotational moments in the ACL deficient state.

Chondral defects of the glenohumeral joint: Long-term outcome after microfracturing of the shoulder.

IntroductionAn increasing number of young patients are diagnosed with chondral lesions. Minimally invasive surgical techniques are important in order to delay progression of the early stages of osteoarthritis and the need for total joint replacement.Materials and methodsPatients (n = 32) who had received microfracturing of the shoulder were retrospectively enrolled, of whom 5 had received shoulder replacements after a mean time of 47 months. Of these patients, 23 completed the Disabilities of the Arm, Shoulder and Hand (DASH) and Constant–Murley Scores in addition to an additional subjective questionnaire. Patients were then clinically examined and received x‑ray analysis of the operated shoulder. Data from an additional 4 patients were acquired by telephone interview.ResultsMean follow-up was 105 months. Of the included patients, 13/27 patients reported no pain, 12/27 patients moderate pain. Of these 12, 6/27 reported pain only at night and 3/27 only during rest. Concerning the outcome of surgery, 19/27 patients were “satisfied” or “very satisfied”. There was a statistically significant increase in internal rotation, but no further differences in the range of motion pre- and postoperatively. Patients without any signs of osteoarthritis before surgery showed statistically significantly better outcomes. There was a statistically significant increase in radiological signs of osteoarthrosis in pre- versus postoperative patients. Patients with bipolar lesions showed statistically significantly poorer Subjective Shoulder Value (SSV) results.ConclusionEven though microfracturing does not prevent radiographic progression, microfracture of the glenohumeral joint might be worth considering as part of a treatment regimen for younger patients who may not yet be treated with arthroplasty.

The Role of the Peripheral Passive Rotation Stabilizers of the Knee With Intact Collateral and Cruciate Ligaments: A Biomechanical Study.

Background:A subset of patients have clinical internal and/or external knee rotational instability despite no apparent injury to the cruciate or collateral ligaments.Purpose/Hypothesis:The purpose of this study was to assess the effect of sequentially cutting the posterolateral, anterolateral, posteromedial, and anteromedial structures of the knee on rotational stability in the setting of intact cruciate and collateral ligaments. It was hypothesized that cutting of the iliotibial band (ITB), anterolateral ligament and lateral capsule (ALL/LC), posterior oblique ligament (POL), and posteromedial capsule (PMC) would significantly increase internal rotation, while sectioning of the anteromedial capsule (AMC) and the popliteus tendon and popliteofibular ligament (PLT/PFL) would lead to a significant increase in external knee rotation.Study Design:Controlled laboratory study.Methods:Ten pairs (N = 20) of cadaveric knees were assigned to 2 sequential cutting groups (group 1: posterolateral-to-posteromedial [PL → PM] and group 2: posteromedial-to-posterolateral [PM → PL]). Specimens were subjected to applied 5-N·m internal and external rotation torques at knee flexion angles of 0°, 30°, 60°, and 90° while intact and after each cut state. Rotational changes were measured and compared with the intact and previous cut states.Results:Sectioning of the ITB significantly increased internal rotation at 60° and 90° by 5.4° and 6.2° in group 1 (PL → PM) and 3.5° and 3.8° in group 2 (PM → PL). PLT/PFL complex sectioning significantly increased external rotation at 60° and 90° by 2.7° and 2.9° in group 1 (PL → PM). At 60° and 90° in group 2 (PM → PL), ALL/LC sectioning produced significant increases in internal rotation of 3.1° and 3.5°, respectively. In group 2 (PM → PL), POL sectioning produced a significant increase in internal rotation of 2.0° at 0°. AMC sectioning significantly increased external rotation at 30° to 90° of flexion with a magnitude of change of <1° in both groups 1 (PL → PM) and 2 (PM → PL).Conclusion:Collectively, the anterolateral corner structures provided primary internal rotation control of the knee from 60° to 90° of knee flexion in knees with intact cruciate and collateral ligaments. The ITB was the most significant primary stabilizer of internal rotation. The POL had a primary role for internal rotational stability at full extension. The PLT/PFL complex was a primary stabilizer for external rotation of the knee at 60° and 90°.Clinical Relevance:This study delineates the primary and secondary roles of the ITB, ALL/LC, POL, and PLT/PFL to rotatory stability of the knee and provides new information to understand knee rotational instabilities.

Three-dimensional motion analysis for validation of shoulder internal rotation.

10% of the points for the Constant-Murley score (CMS) are allocated for the capacity for internal rotation (IR), measured as unassisted active movement of the dorsum of the hand or the thumb to reach different anatomical landmarks. However, there is little information about the validity of this method and no three-dimensional measurement of the degree of IR that is necessary to reach these landmarks. Sixteen volunteers with healthy shoulders were recruited. The degree of IR was defined using the following landmarks as described in the CMS: (1) lateral aspect of thigh, (2) buttock, (3) sacroiliac joint, (4) level of waist, (5) vertebra T12, (6) interscapular. The validity of IR measurement was assessed by simultaneous 3D motion analysis. Using the thumb as pointer, there were significant increases in IR from 39.3° at position 1 to 80.4° at position 2, followed by 105.1°, 108.6°, 110.1°, and 125.3° at position 3-6. Taking the dorsum of the hand as pointer, there were significant increases in IR between all positions, starting from 71.2° (position 1) and followed by 99.3°, 104.1°, 110.3°, 115.2°, and 119.7° at positions 2 to 6. Comparing the two measurement methods, a significant difference was found for the amount of IR between positions 1 and 2. Measurement of IR as described in the CMS is a suitable method. However, there was an increase of only 10° in IR between positions 3 and 5, which may be hard to measure with a standard goniometer in clinical practice.

Internal and External Rotation Stabilizers of the Knee with Intact Cruciate and Collateral Ligaments

Objectives:The purpose of this study was to assess the effect of sequentially cutting the posterolateral, anterolateral, posteromedial and anteromedial structures of the knee on rotational kinematics in the setting of intact cruciate and collateral ligaments. It was hypothesized that cutting of the iliotibial band (ITB), anterolateral ligament and lateral capsule (ALL/LC), the posterior oblique ligament (POL), and the posteromedial capsule (PMC) would significantly increase internal rotation and that the anteromedial capsule (AMC), and the popliteus tendon and popliteofibular ligament (PLT/PFL) when sectioned would lead to a significant increase in external rotation of the knee.Methods:Ten pairs (n = 20) of cadaveric knees were assigned to two sequential cutting groups (posterolateral-to-posteromedial and posteromedial-to-posterolateral). Specimen were subjected to 5 N-m of internal and external rotation torque at knee flexion angles 0° through 90° in the intact and after each cut state. Rotational changes were measured and compared to the intact and previous states following each cut.Results:Sectioning of the ITB significantly increased internal rotation at 60° and 90° by 5.4° and 6.2[[Unsupported Character - Codename ­]]°, respectively (after ALL/LC cut) and 3.5° and 3.8° (prior to ALL/LC cut) (Figure 1). At 60° and 90°, section of the ALL/LC produced significant increases in internal rotation of 3.1[[Unsupported Character - Codename ­]]° and 3.5°, respectively (after ITB cut) and of 0.5° (prior to ITB cut) (Figure 1). At 0°, section of the POL produced significant increases in internal rotation of 2.0° (ITB intact) and 1.8° (after ITB cut) (Figure 1). Sectioning the PLT/PFL complex significantly increased external rotation at 60° and 90° by 2.7° and 2.9°, respectively (prior to sectioning medial structures) and 2.2° and 2.7[[Unsupported Character - Codename ­]]°, respectively (after sectioning medial structures) (Figure 2). Sectioning the AMC produced significant increases in external rotation at 30°- 90° of flexion, however the magnitude of change was < 1° (Figure 2).Figure 1.Changes in internal rotation from the intact state during a 5 N-m internal rotation torque when sequentially cutting structures from lateral to medial (above) and medial to lateral (below).Figure 2.Changes in external rotation from the intact state during a 5 N-m external rotation torque when sequentially cutting structures from lateral to medial (above) and medial to lateral (below).Conclusion:Collectively the anterolateral corner structures had a primary role in internal rotational control of the knee from 60° to 90° of knee flexion. The ITB was the most significant primary stabilizer for internal rotation in ACL intact knees. The POL contributed to internal rotational control at full extension, while the PLT/PFL complex controlled external rotation of the knee at higher flexion angles (60° and 90°). Internal rotation control of the knee has been mainly attributed to the cruciate and collateral ligaments. This study delineates the primary and secondary roles of the ITB, the ALL/LC, POL and PLT/PFL to rotatory stability of the knee. As such, it provides new information about the understanding of rotational instabilities of the knee.

The Involvement of the Anterolateral Ligament in Rotational Control of the Knee

Background: Rotational control of the knee is crucial for knee stability. The anterolateral ligament (ALL) has been identified as a potentially important structure involved in rotational control of the knee. Purpose/Hypothesis: The purpose of this study was to determine, utilizing a navigation system, the involvement of the anterior cruciate ligament (ACL), the iliotibial band (ITB), and the ALL in tibial internal rotational control of the knee. The hypothesis was that the ALL would be involved in rotational control of the knee at varying degrees of knee flexion. Study Design: Controlled laboratory study. Methods: Twelve fresh-frozen cadaveric knees were tested in internal rotation at 20° and 90° of flexion and then subsequently tested using a simulated pivot-shift test consisting of coupled axial rotation at 30° of flexion. Serial sectioning of the ACL, ALL, and ITB was performed. On the contralateral knee, sectioning was performed in the reverse order. Measurements were collected using a surgical navigation system before and after each sectioning. Results: After ACL sectioning, an incision of the ALL induced a significant increase in internal rotation (+19.2% [P = .0002] at 20°; +21.8% [P = .0029] at 90°) and in coupled axial rotation (+43.0%; P = .0035) compared with the intact knee as well as a significant increase in internal rotation at 90° (+13.4%; P = .009) and in coupled axial rotation (+30.8%; P = .0124) compared with the ACL-deficient knee. After ITB sectioning, an additional ALL section caused a significant increase in internal rotation (+39.0% [P = .002] at 20°; +63.0% [P = .0147] at 90°) and in coupled axial rotation (+59.7%; P = .0003) compared with the intact knee as well as a significant increase in internal rotation at 90° (+14.8%; P = .0067) in comparison to the ITB-deficient knee. Conclusion: The ALL is involved in rotational control of the knee at varying degrees of knee flexion and during a simulated pivot shift. Concomitant to an ACL or ITB transection, sectioning the ALL further increased rotational laxity. Clinical Relevance: This laboratory study demonstrated that the ALL provides rotational control of the knee in combination with the ACL and/or ITB.

Effects of Muscle Energy Technique in Increasing Range of Motion and Strength of Glenohumeral Internal Rotator, in Athletes with Glenohumeral Internal Rotation Deficit

<i>Study design: </i>Randomized control trial. <i>Objective: </i>To measure the effect muscle energy technique(MET) for the glenohumeral joint external rotators to improve the range of motion and strength of internal rotators in athletes with glenohumeral internal rotation deficit (GIRD). <i>Background: </i>Glenohumeral internal rotation deficit is one of the leading causes of impairments in overhead throwing athletes. Anatomical GIRD is though considered to be normal in overhead athletes but it may further lead to osseous and capsuloligamentous changes in the glenohumeral joint if not treated. The muscle energy technique protocol aimed at improving the range of motion and strength of the internal rotators of the glenohumeral joint. It has been hypothesized that MET will increase the glenohumeral internal rotation ROM and strength in athletes with GIRD. <i>Methods: </i>thirty overhead athletes were conveniently assigned in two groups. MET for glenohumeral joint external rotators (n=15) and stretching for glenohumeral joint external rotators (n=15). We measured the range of motion of glenohumeral joint internal rotation and strength of glenohumeral joint internal rotators, of the dominant shoulder at 0 day, 1^st week and 2^nd week. At the end of 2^nd week data analysis was done using one way ANOVA and post hoc tukey’s test and significant results were found. (p < 0.05). <i>Results: </i>The group treated with MET for the external rotators had a significant increase in internal rotation at the end of 2^nd week. The group treated with stretching for external rotators do not showed a significant increase in internal rotation. <i>Conclusion: </i>It is concluded that MET is an effective treatment for increasing the ROM and strength of internal rotation at the glenohumeral joint in asymptomatic overhead athletes. Therefore application of MET for the external rotators may be useful for increasing the ROM as well as strength in overhead athletes.

An In Vitro Robotic Assessment of the Anterolateral Ligament, Part 1

Background: Recent investigations have described the structural and functional behavior of the anterolateral ligament (ALL) of the knee through pull-apart and isolated sectioning studies. However, the secondary stabilizing role of the ALL in the setting of a complete anterior cruciate ligament (ACL) tear has not been fully defined for common simulated clinical examinations, such as the pivot-shift, anterior drawer, and internal rotation tests. Hypothesis: Combined sectioning of the ALL and ACL would lead to increased internal rotation and increased axial plane translation during a pivot-shift test when compared with isolated sectioning of the ACL. Study Design: Controlled laboratory study. Methods: Ten fresh-frozen human cadaveric knees were subjected to a simulated pivot-shift test with coupled 10-N·m valgus and 5-N·m internal rotation torques from 0° to 60° of knee flexion and a 5-N·m internal rotation torque and an 88-N anterior tibial load, both from 0° to 120° of knee flexion via a 6 degrees of freedom robotic system. Kinematic changes were measured and compared with the intact state for isolated sectioning of the ACL and combined sectioning of the ACL and ALL. Results: Combined sectioning of the ACL and ALL resulted in a significant increase in axial plane tibial translation during a simulated pivot shift at 0°, 15°, 30°, and 60° of knee flexion and a significant increase in internal rotation at 0°, 15°, 30°, 45°, 60°, 75°, 90°, 105°, and 120° when compared with the intact and ACL-deficient states. Based on the model results, ALL sectioning resulted in an additional 2.1 mm (95% CI, 1.4-2.9 mm; P < .001) of axial plane translation during the pivot shift when compared with ACL-only sectioning, when pooling evidence over all flexion angles. Likewise, when subjected to IR torque, the ACL+ALL-deficient state resulted in an additional 3.2° of internal rotation (95% CI, 2.4°-4.1°; P < .001) versus the intact state, and the additional sectioning of the ALL increased internal rotation by 2.7° (95% CI, 1.8°-3.6°; P < .001) versus the ACL-deficient state. Conclusion: The results of this study confirm the ALL as an important lateral knee structure that provides rotatory stability to the knee. Specifically, the ALL was a significant secondary stabilizer throughout flexion during an applied internal rotation torque and simulated pivot-shift test in the context of an ACL-deficient knee. Clinical Relevance: Residual internal rotation and a positive pivot shift after ACL reconstruction may be attributed to ALL injury. For these patients, surgical treatment of an ALL tear may be considered.

Kinematic Analysis of the Posterior Cruciate Ligament, Part 1

Background: The posterior cruciate ligament (PCL) is composed of 2 functional bundles and has an essential role in knee function and stability. There is, however, a limited understanding of the role of each individual bundle through the full range of knee flexion. Hypothesis: Both bundles provide restraint to posterior tibial translation across a full range of knee flexion. At higher angles of knee flexion (>90°), the intact PCL also imparts significant rotational stability. Study Design: Controlled laboratory study. Methods: Twenty matched-paired, human cadaveric knees (mean age, 55.2 years; range, 51-59 years; 6 male and 4 female pairs) were used to evaluate the kinematics of an intact, anterolateral bundle (ALB) sectioned, posteromedial bundle (PMB) sectioned, and complete PCL sectioned knee. A 6 degree of freedom robotic system was used to assess knee stability with an applied 134-N posterior tibial load, 5-N·m external and internal rotation torques, 10-N·m valgus and varus torques, and a coupled 100-N posterior tibial load and 5-N external rotation torque at 0°, 15°, 30°, 45°, 60°, 75°, 90°, 105°, and 120°. Results: All sectioned states had significant increases compared with intact in posterior translation, internal rotation, and external rotation at all tested flexion angles, with the exception of the ALB sectioned state at 75° of flexion for external rotation. The significant increases (mean ± standard deviation) in posterior translation during a 134-N posterior tibial load at 90° of flexion were 0.9 ± 0.6 mm, 2.6 ± 1.8 mm, and 11.7 ± 4.0 mm for the PMB, ALB, and complete PCL sectioned states, respectively, compared with the intact state. The largest significant increases in internal rotation were in the PMB and complete PCL sectioned states at 105° of flexion, 1.3° ± 1.0° and 2.8° ± 2.1°, respectively. Conclusion: Both the ALB and the PMB assume a significant role in resisting posterior tibial translation, at all flexion angles, suggesting a codominant relationship. The PCL provided a significant constraint to internal rotation beyond 90° of flexion. Clinical Relevance: This information broadens the understanding of native knee kinematics and provides a template for the evaluation of single- and double-bundle PCL reconstructions.

Is Arthroscopic Coracoplasty Necessary in Subcoracoid Impingement Syndrome?

The purpose of this study was to analyze the outcomes of arthroscopic coracoplasty in the treatment of subcoracoid impingement syndrome. We compared 23 shoulders that underwent arthroscopic coracoplasty for the treatment of subcoracoid impingement syndrome with 28 shoulders that did not undergo arthroscopic coracoplasty for the treatment of subcoracoid impingement syndrome, which comprised the control group. All the shoulders had subcoracoid and subacromial impingement syndrome with or without rotator cuff tear. Subcoracoid impingement was defined as a coracohumeral distance of less than 6 mm on the preoperative magnetic resonance image with anterior shoulder pain or tenderness. The 2 groups were further divided into several subgroups according to the size of concomitant rotator cuff tear, and a comparative analysis of functional outcomes after surgery among the subgroups was performed. In the 2 groups, the overall functional outcomes improved after surgery. The study group showed a significant increase in internal rotation compared with that in the control group (P = .001) at the last follow-up. The large to massive rotator cuff tear subgroup of the study group showed a significant increase in internal rotation (P = .017). On the other hand, no significant difference was seen in the subgroups with small to medium rotator cuff tears including isolated subscapularis tears. The no rotator cuff tear subgroup of the study group showed a significant increase in internal rotation (P = .046). Arthroscopic coracoplasty for subcoracoid impingement syndrome can provide a satisfactory outcome. In particular, a significant increase in internal rotation of the treated group was achieved after surgery in comparison with the untreated group, especially in the large to massive rotator cuff tear subgroup and in the no rotator cuff tear subgroup. Level III, retrospective comparative study.

Glenohumeral Range of Motion in Major League Pitchers

Background:Although overhead throwing athletes may develop unique glenohumeral range of motion characteristics, to our knowledge these characteristics have not been studied longitudinally in major league pitchers.Hypothesis:Major league pitchers (starters and relievers) experience an increase in glenohumeral external rotation and a decrease in internal rotation and total range of motion. Glenohumeral internal rotation deficit worsens over a regular playing season.Study Design:Retrospective cohort study.Methods:In 21 major league baseball pitchers (29 individual playing seasons), glenohumeral range of motion was measured in external and internal rotation for the throwing and nonthrowing shoulders before and at the conclusion of the regular season. The total range of motion (the sum of external rotation and internal rotation) and the glenohumeral internal rotation deficit were calculated (the difference between internal rotation of the nonthrowing shoulder minus that of the throwing shoulder), and data were compared between starting and relief pitchers.Results:The overall mean changes in external rotation (+1.5°), internal rotation (+2.7°), and total range of motion (+3.3°) were not statistically significant. However, starting pitchers showed statistically significant increases in internal rotation (+6.5°, P = 0.01) and total range of motion (+7.9°, P = 0.04), whereas relief pitchers had significant worsening of glenohumeral internal rotation deficit (+5.3°, P = 0.04).Conclusions:The characteristics of glenohumeral range of motion in major league pitchers did not differ significantly from the beginning to the end of a season, but significant changes did occur between starting and relief pitchers.Clinical Relevance:Adaptations to the daily routines of starter and reliever pitchers may be warranted on the basis of these findings.

Anatomic Posterolateral Knee Reconstructions Require a Popliteofibular Ligament Reconstruction Through a Tibial Tunnel

Background: No biomechanical study has been performed analyzing the merits of reconstructing the popliteofibular ligament (PFL) through a tibial tunnel with an anatomic reconstruction of the posterolateral knee. Hypothesis: There is no difference in an anatomic posterolateral knee reconstruction with or without a PFL reconstruction placed through a tibial tunnel in restoring knee motion to the intact, uninjured state, and the knee is not overconstrained with this reconstruction. Study Design: Controlled laboratory study. Methods: Eight paired knees were tested in the intact state and then sectioned to simulate a grade III posterolateral knee injury. The reconstruction for the first paired knee reconstructed the PFL (through a tibial tunnel), popliteus tendon, and fibular collateral ligament (group 1); the matched knee reconstruction involved only the popliteus tendon and fibular collateral ligament (group 2). Results: Reconstructions for group 1 knees restored knee motion to the intact state for all tested conditions at all knee flexion angles with no overconstraint of the knee. Without reconstructing the PFL (group 2), small but significant increases in motion were found for varus translation at 0° (3.0°), 20° (3.1°), and 60° (3.8°) of knee flexion compared with the intact state. At 60° and 90° of flexion, the reconstruction for group 2 had small but significant increases in internal rotation compared with the intact state (1.3° and 1.8°, respectively). Conclusion: Inclusion of the PFL through a tibial tunnel as part of an anatomic posterolateral knee reconstruction restores knee stability back to the intact state and does not overconstrain the knee. Furthermore, inclusion of the PFL through a tibial tunnel restored normal internal rotation. Clinical Relevance: The PFL should be included in anatomic reconstructions of grade III posterolateral knee injuries with placement through a tibial tunnel to best restore the intact, preinjury knee motion state and, most notably, normal internal rotation without evidence of overconstraint of the knee.

Analysis of the Static Function of the Popliteus Tendon and Evaluation of an Anatomic Reconstruction

Background The popliteus tendon has important dynamic and static stabilizing functions at the knee. Evaluation of its static role as the “fifth ligament” of the knee and a subsequent analysis of a popliteus tendon reconstruction has not been performed. Hypothesis In vitro knee stability can be restored to a popliteus tendon—deficient knee with an anatomic popliteus tendon reconstruction. Study Design Controlled laboratory study. Methods Eleven nonpaired cadaveric knees were tested under the following popliteus tendon states: intact, sectioned, and reconstructed using an autogenous semitendinosus graft. Each knee was subjected to 10-N·m varus moments, 5-N·m external and internal torques, and 88-N anterior and posterior loads at flexion angles of 0°, 20°, 30°, 60°, and 90°. A 6 degrees of freedom electromagnetic motion tracking system was used to assess motion changes of the tibia with respect to the femur. Results Significant increases in external rotation and small but significant increases in internal rotation, varus angulation, and anterior translation motion were found after sectioning the popliteus tendon compared to the intact state. Significant decreases in external rotation were found in the reconstructed state compared with the sectioned state at knee flexion angles of 20°, 30°, 60°, and 90°. Comparing the reconstructed state to the intact state, there were no significant differences at knee flexion angles of 0° and 20°, but significant decreases of external rotation were found at knee flexion angles of 30°, 60°, and 90°. Additionally, there were small but significant differences between the reconstructed and intact state with respect to varus angulation at knee flexion angles of 20°, 30°, and 60°; anterior translation at 20° and 30°; and internal rotation at all flexion angles. Conclusion The popliteus tendon has important primary stabilization roles at the knee. The authors also found that an anatomic popliteus tendon reconstruction significantly reduced the increase in external rotation that occurred with sectioning the popliteus tendon; however, differences seen with respect to internal rotation, varus angulation, and anterior translation were not restored. Clinical Significance The popliteus tendon functions essentially as the fifth major ligament of the knee. An anatomic popliteus tendon reconstruction can restore external rotation stability to knees with popliteus tendon injury.

An in Vitro Analysis of an Anatomical Medial Knee Reconstruction

Background An anatomical medial knee reconstruction has not been described in the literature. Hypothesis Knee stability and ligamentous load distribution would be restored to the native state with an anatomical medial knee reconstruction. Study Design Controlled laboratory study. Methods Ten nonpaired cadaveric knees were tested in the intact, superficial medial collateral ligament and posterior oblique ligament—sectioned, and anatomically reconstructed states. Each knee was tested at 0°, 20°, 30°, 60°, and 90° of knee flexion with a 10-N·m valgus load, 5-N·m external and internal rotation torques, and 88-N anterior and posterior drawer loads. A 6 degrees of freedom electromagnetic motion tracking system measured angulation and displacement changes of the tibia with respect to the femur. Buckle transducers measured the loads on the intact and reconstructed proximal and distal divisions of the superficial medial collateral ligament and the posterior oblique ligament. Results A significant increase was found in valgus angulation and external rotation after sectioning the medial knee structures at all tested knee flexion angles. This was restored after an anatomical medial knee reconstruction. The authors also found a significant increase in internal rotation at 0°, 20°, 30°, and 60° of knee flexion after sectioning the medial knee structures, which was restored after the reconstruction. A significant increase in anterior translation was observed after sectioning the medial knee structures at 20°, 30°, 60°, and 90° of knee flexion. This increase in anterior translation was restored following the reconstruction at 20° and 30° of knee flexion, but was not restored at 60° and 90°. A small, but significant, increase in posterior translation was found after sectioning the medial knee structures at 0° and 30° of knee flexion, but this was not restored after the reconstruction. Overall, there were no clinically important differences in observed load on the ligaments when comparing the intact with the reconstructed states for valgus, external and internal rotation, and anterior and posterior drawer loads. Conclusion An anatomical medial knee reconstruction restores near-normal stability to a knee with a complete superficial medial collateral ligament and posterior oblique ligament injury, while avoiding overconstraint of the reconstructed ligament grafts. Clinical Significance This anatomical medial knee reconstruction technique provides native stability and ligament load distribution in patients with chronic or severe acute medial knee injuries.

In Vivo Kinematics of the Tibiotalar Joint After Lateral Ankle Instability

Background Previous studies have suggested that injury to the anterior talofibular ligament (ATFL) may be linked to altered kinematics and the development of osteoarthritis of the ankle joint. However, the effects of ATFL injury on the in vivo kinematics of the ankle joint are unclear. Hypothesis Based on the orientation of the ATFL fibers, ATFL deficiency leads to increased anterior translation and increased internal rotation of the talus relative to the tibia. Study Design Descriptive laboratory study. Methods The ankles of 9 patients with unilateral ATFL injuries were compared as they stepped onto a level surface. Kinematic measurements were made as a function of increasing load. With use of magnetic resonance imaging and orthogonal fluoroscopy, the in vivo kinematics of the tibiotalar joint were measured in the ATFL-deficient and intact ankles of the same individuals. Results A statistically significant increase in internal rotation, anterior translation, and superior translation of the talus was measured in ATFL-deficient ankles, as compared with the intact contralateral controls. For example, at 100% body weight, ATFL-deficient ankles demonstrated an increase of 0.9 ± 0.5 mm in anterior translation (P = .008), an increase of 5.7° ± 3.6° in internal rotation (P = .008), and a slight increase of 0.2 ± 0.2 mm in the superior translation (P = .02) relative to the intact contralateral ankles. Conclusion Deficiency of the ATFL increases anterior translation, internal rotation, and superior translation of the talus. Clinical Relevance Altered kinematics may contribute to the degenerative changes observed with chronic lateral ankle instability. These findings might help to explain the degenerative changes frequently observed on the medial talus in patients with chronic ATFL insufficiency and so provide a baseline for improving ankle ligament reconstructions aimed at restoring normal joint motion.

Forthcoming Issues

No consensus exists about the management of massive and symptomatic rotator cuff tears (RCTs). The objective of this study was to compare the 12-month clinical outcomes of various treatment options for massive RCTs.Arthroscopic surgery has a role to play in the treatment of massive and apparently irreparable RCTs.A prospective multicentre non-randomised study was performed in patients with massive RCTs managed non-operatively (NONOP) or by arthroscopic tenotomy/tenodesis of the long head of biceps (aTLB), arthroscopic partial tendon repair (aPTR), arthroscopic latissimus dorsi transfer (aLDT), or reverse shoulder arthroplasty (RSA). Clinical outcomes were evaluated based on the Constant score, Subjective Shoulder Value (SSV), and American Shoulder and Elbow Surgeons (ASES) score after 3, 6, and 12 months.The 218 included patients (mean age, 69 years) were distributed as follows: NONOP, n = 71; aTLB, n = 26; aPTR, n = 61; aLDT, n = 25; and RSA, n = 35. After 12 months, the mean Constant score, SSV, and ASES score values were 70, 68%, and 73, respectively, and had improved significantly versus the preoperative values in all treatment groups. RSA was the only treatment followed by improvements in all Constant score items. Active forwards elevation improved significantly in the NONOP (+25°), aPTR (+26°), and RSA (+66°) groups. An improvement in active external rotation was seen only in the RSA group, where it was small (+10°, p = 0.046). Significant increases in internal rotation were seen in the NONOP (+1.6 points) and aPTR (+1.7 points) groups.Arthroscopic techniques (aTLB, aPTR, and aLDT) for managing massive irreparable RCTs produce significant functional gains. Partial tendon repair (aPTR) and RSA may provide better outcomes than isolated aTLB or aLDT.III, non-randomised prospective study.