Medial Subluxation Research Articles

Association of Tarsometarsal Joint Slippage Following Minimally Invasive Bunionectomy with Removal of Hardware

Category: Bunion; Midfoot/Forefoot Introduction/Purpose: Following Minimally Invasive Bunionectomy (MISB), removal of hardware rates are about 5% and commonly due to midfoot pain near the distal metatarsal screw site. This distal screw head site corresponds to the proximal midshaft width measurement location, which has shown to increase postoperatively. One explanation for this increased width is medial subluxation of the first metatarsal at the tarsal-metatarsal (TMT) joint. This “TMT slippage” occurs as the metatarsal base is shifted medially to accommodate the metatarsal head lateralization at the metatarsal phalangeal joint. The force across the TMT joint overcomes the ligamentous stabilizers, allowing the metatarsal to “slip.” The aim of this study was to investigate the relation between TMT slippage and removal of hardware (ROH) rates. Methods: A retrospective analysis of prospectively collected data identified 38 patients undergoing MISB for hallux valgus (HV) with subsequent distal chevron screw removal and a control group of 40 MISB cases without hardware removal. Demographic data and surgical details were obtained via chart review. Pre- and at least 6-month post-operative radiographs were measured to obtain transverse TMT slippage on anteroposterior (AP) radiographs (Figures 1). Additionally, distal foot width, midshaft foot width, hallux valgus angle (HVA) and intermetatarsal angle (IMA) were measured. Independent samples t-tests and chi-square analyses were used to compare continuous and categorical characteristics, respectively, between patients who underwent removal of hardware. Multivariable logistic regression modeling was used to identify risk factors for undergoing hardware removal. Results: Interobserver reliability, measured by intraclass correlation coefficients (ICCs), was high for all measurements (ICC > 0.70). The change in TMT slip was significantly higher in the hardware removal (ROH) group compared to the control group (+1.39 versus +0.80, p=0.004) (Table 1). A greater decrease in distal foot width (narrower distal width postoperatively) was associated with an increased likelihood of hardware removal (OR: 0.76), while smaller reductions in HVA and IMA were linked to a higher likelihood of requiring ROH (OR: 1.12 and 1.42, respectively). Notably, a larger increase in TMT slip correlated with the highest likelihood of being in the ROH cohort (OR: 2.87) (Table 2). TMT slippage did not correlate with any other measurements (all p > 0.05). Conclusion: Our study highlights the relationship between MISB outcomes and TMT slippage. Patients requiring distal chevron screw removal showed significantly higher transverse TMT slippage. Interestingly, a smaller distal foot width reduction was associated with decreased hardware removal likelihood, suggesting a potential protective mechanism. Conversely, smaller corrections of both HVA and IMA were associated with higher chances of hardware removal. Notably, for every 1-centimeter increase in TMT slippage postoperatively, there was a nearly 3-fold increase in the likelihood of distal chevron screw removal. Further research is needed to understand the mechanisms underlying TMT slippage and its impact on HV correction outcomes.

Is It Time to Rethink the Relationship Between Subscapularis Tears and the Long Head of Biceps Tendon?

Introduction Pre-operative diagnosis of subscapularis tears remains a difficult challenge. Ultrasound has been shown to be ineffective at directly detecting subscapularis tears. It has been widely accepted that medial subluxation of the long head of biceps tendon (LHBT) is associated with full-thickness subscapularis tears. The aims of this study are to assess whether LHBT subluxation on ultrasound scanning has any predictive value for subscapularis tears and to determine the relationship between LHBT subluxation and subscapularis tears at arthroscopy. Methods Pre-operative ultrasound and arthroscopic findings for patients undergoing arthroscopic rotator cuff repair at our institution between March 2011 and January 2016 were analysed. The accuracy of LHBT subluxation on ultrasound and at arthroscopy as a predictor of subscapularis tears at arthroscopy was calculated. The correlation between LHBT subluxation and subscapularis tears was determined. A standardised technique was used for ultrasound scans, and the grade of the sonographer was recorded. Results Three hundred fifty-nine rotator cuff repairs were performed. Twenty-four patients had a subluxed LHBT. Ultrasound was poorly sensitive (50%), and a subluxed LHBT on ultrasound only correlated very weakly with subscapularis tears at arthroscopy (R = 0.268, p<0.001). At arthroscopy, 92 patients had full-thickness subscapularis tears. Of these, only 16 patients (17%) had a subluxed/dislocated LHBT. Of the 24 patients with a subluxed LHBT, eight had no subscapularis tears. Thus, LHBT subluxation/dislocation only correlated weakly with full-thickness subscapularis tears (R=0.252, p<0.001). Conclusion Due to their close anatomical relationship, traditional teaching suggests subscapularis tears are associated with medial LHBT subluxation. Our data indicate that, contrary to popular belief, the two are only weakly correlated. In our series, the majority of patients with subscapularis tears (83%) had their LHBT in-groove. The authors therefore recommend high vigilance during arthroscopy for the diagnosis and repair of subscapularis tears, regardless of pre-operative ultrasound findings and the intra-operative position of the LHBT.

The Keystone of Muller Weiss Disease: How Does the Compressed Navicular Cause the Cascade of Deformities in the Mid and Hind Foot?

Category: Hindfoot; Midfoot/Forefoot Introduction/Purpose: It is believed that Müller Weiss Disease (MWD) starts with narrowing of the lateral and dorsal side of the navicular, followed by lateral rotation and slight dorsal lifting of the talar head and medial rotation of the navicular, a varus heel, and ultimately additional changes in the hindfoot and midfoot. This study used the technique of distance mapping to measure the space of the “peri-navicular” joints on an averaged 3D foot model for both normal controls and a group of MWD feet, to prove the key pathologic changes of MWD. Methods: Weight bearing Scans of 55 health feet without deformities, trauma and surgical history, and 69 feet with MWD were included in this study. The Bonelogic program (Disior, Paragon28) was used to automatically segment the bones and 3D information of each foot in the same group was pooled to create an average foot model for both the controls and the MWD feet. On the two foot models, distance mapping was applied and compared to compare the space of the perinavicular joints (the talonavicular joint, the three navicular cuneiform joints, and the calcaneocuboid joint). The morphology of the navicular bone and the talonavicular articulation in the two groups were also studied. Results: In the MWD foot model, there was significant narrowing of the lateral pole and the dorsal side of the navicular compared with the average normal foot model. The bone articular surfaces of the two foot models matched well, meaning that the deformity changes occurred predominantly to the shape of the navicular but not the contour of the joint surface. The joint space measured using distance mapping was significantly greater in the talonavicular joint, middle and lateral naviculocuneiform joints, and the calcaneocuboid joint in the MWD feet than in normal controls. There was no difference in the joint space of the medial naviculocuneiform joint between the two foot models. Conclusion: It is the change in the shape of navicular bone but not articular surface contour which causes the development of the cascade of deformities in MWD. The sequalae includes increased joint space on both sides of navicular tail, and in the calcaneocuboid joint, lateral subluxation of the talus head, relative medial subluxation of the navicular, a varus heel with more opening in the sinus tarsi, proximal shift of the calcaneal tuberosity, a flat medial arch with subsidence at the talonavicular joint, decreased adduction of the forefoot, medial translation of the cuboid at the calcaneocuboid articulation, and a shortened 1st metatarsal.

Rare case of intra-articular biceps incarceration following traumatic massive rotator cuff tear

Rare case of intra-articular biceps incarceration following traumatic massive rotator cuff tear

Lateral Patellofemoral Ligament Reconstruction With Semitendinosus Allograft in the Setting of Previous Lateral Release

The lateral patellofemoral ligament acts to resist medial displacement of the patella. When medial subluxation occurs, it usually has an iatrogenic cause such as prior lateral release, an over-tightened medial patellofemoral ligament reconstruction, or detachment of the vastus lateralis from the patella. The justification for lateral retinacular release has historically been to address extensor mechanism issues such as imbalance of the mechanism due to increased retinacular tension. We present a Technical Note on the treatment of chronic medial patellar instability due to a previous lateral retinacular release using a soft-tissue reconstruction approach with a semitendinosus allograft.

Clinical treatment of dorsal avulsion fracture of the capitellum combined with medial or posterior medial dislocation of the elbow joint

To analyze the possible injury mechanisms in patients with dorsal avulsion fracture of the capitellum combined with medial or posterior medial dislocation of the elbow joint, and to discuss their treatment and prognosis. Retrospective analysis was made on the clinical data of 4 patients with dorsal avulsion fracture of the capitellum combined with medial or posterior medial dislocation of the elbow joint admitted between September 2014 and September 2020, including 3 males and 1 female with an average age of 20.7 years (range, 13-32 years). There were 2 cases of dorsal avulsion fracture of the capitellum combined with medial dislocation of the elbow joint and 2 cases of dorsal avulsion fracture of the capitellum and anterior medial fracture of the coronoid process combined with posterior medial subluxation of the elbow joint. Closed reduction was performed in 3 patients with fresh fracture combined with dislocation, then 2 cases were fixed with tension band and 1 case was fixed with tension band combined with Acumed coronoid anatomic plate. And in patient with old fracture nonunion, the coronoid process was fixed with 1 screw, then the humeral sclerotic bone mass was removed, and finally the lateral collateral ligament was repaired and a hinged external fixator was added. All the incisions healed by first intention without early complications such as infection or peripheral nerve injury. The 4 patients were followed up 13-30 months (mean, 20.8 months). The fractures all healed with a healing time of 70-90 days (mean, 79.5 days). At 6 months after operation, heterotopic ossification was seen in the posterior aspect of the right elbow joint in 1 case, and the alkaline phosphatase level was normal (67 U/L); the tension band was removed to clear the heterotopic ossification and the elbow joint was released. The rest of the patients had no heterotopic ossification. At last follow-up, all patients had good functional recovery of the elbow joint, with a Mayo score of 85-100 (mean, 92.5), and the excellent and good rate was 100%. The elbow flexion range of motion was 120°-135°, the extension range of motion was 10°-20°, and the pronation and supination range of motion were all 75°-85°. Dorsal avulsion fractures of the capitellum combined with medial or posterior medial dislocation of the elbow may be due to simple varus stress. If an anteromedial coronoid facet fracture also occurs, it may be for the varus posteromedial rotatory instability, which is the opposite mechanism to that of an Osborne-Cotterill lesion. For fresh dorsal avulsion fractures of the capitellum, tension band fixation can be used with good results.

Hindfoot Varus Deformity: An Essential but Easily Neglected Pathological Change in Müller-Weiss Disease

Category:Hindfoot; Midfoot/Forefoot; OtherIntroduction/Purpose:The key pathology of Müller-Weiss Disease (MWD) is fragmentation of the lateral pole of the navicular which leads to lateral rotation of the talar head, inversion of the subtalar joint, and eventually collapse of the medial arch with a paradoxical flatfoot deformity since the varus heel persists. Treatment for MWD should be based on an understanding of this unusual hind and midfoot deformity in order to achieve ideal outcomes. For years however, some authors have treated MWD as a flatfoot deformity instead of correction of the varus heel. This study used weightbearing CT (WBCT) images to demonstrate the structural and alignment changes of the hindfoot and medial arch in patients with MWD compared to those of controls and patients with adult acquired flatfoot deformity (AAFD).Methods:Twelve patients with 17 feet from two medical centers with a clinical diagnosis of MWD were retrospectively reviewed. Ten feet with flexible AAFD were chosen as the flatfoot control group. Ten feet without deformity, arthritis, a history of trauma, or prior surgical history in the foot and ankle were chosen as normal controls. The hindfoot moment arm (HMA), foot and ankle offset (FAO), middle facet subluxation (MFS), talonavicular joint coverage angle (TNCA), and the percentage of calcaneocuboid joint subluxation (CCS) measured on WBCT were used to assess the alignment of the hindfoot and peritalar joints. The arch height index was used to assess the height of the medial arch. Positive was used to reflect lateral subluxations and negative was for the medial ones. ANOVA test were used to compare data among the three groups with a normal distribution, while Wilcoxon test were used for non normal distribution.Results:According to WBCT analysis, patients with MWD showed totally different hindfoot alignment and peritalar subluxation characteristics compared to the AAFD and the normal control groups. In the order of MWD, AAFD and control, the mean HMA values were -3.44 mm, 15.75 mm, and 3.19 mm, FAO values were -0.72%, 7.42%, and 2.63%. TNCA values were -7.18, 22.11, and 11.37; MFS values were 14%, 45%, and 23%; CCS values were -0.19, 0 and -0.04. The arch height index values were 0.46, 0.45, and 0.58. There was statistically significant difference among the three groups in all the above parameters except the middle facet subluxation and fifth metatarsal medial cuneiform height ratios between the MWD group and the normal controls.Conclusion:This study confirmed that hindfoot varus is a typical feature of MWD. And this is the first study to demonstrate that peritalar subluxation is an important marker. With lateral rotation of the talar head, the subtalar joint is driven into varus, with medial subluxation of both the middle facet and the calcaneocuboid joint, resulting in peritalar subluxation opposite to that of AAFD. No significant difference between the medial arch of the MWD group and the controls was present. In conclusion, structural changes of the midfoot and hindfoot totally different from the characteristics of AAFD are present in MWD.

Coronal subluxation of the tibiofemoral joint before and after anterior cruciate ligament reconstruction

BackgroundStudies have shown that medial subluxation of the tibia occurs after anterior cruciate ligament (ACL) rupture. However, it is unclear whether anterior cruciate ligament reconstruction (ACLR) can correct tibial coronal subluxation.PurposeTo determine whether the tibia is medially subluxated after ACL rupture, and whether ACLR can correct medial subluxation of the tibia.Study designCase series; Level of evidence, 4, Retrospective clinical study.MethodsThe distance of tibial coronal subluxation before and after ACLR surgery was measured in 48 patients with ACL rupture and meniscus injury. Tibiofemoral subluxation was defined as the perpendicular distance between the long axis of the tibia and a second parallel line originating at the most proximal aspect of the femoral intercondylar notch. To determine the long axis of the tibia, two circles separated by 5 cm were centered on the proximal tibia. The proximal circle is 5 cm from the tibial plateau, and the distal circle is 5 cm from the proximal circle. The line passing through the center of the two circles was considered the long axis of the proximal tibia. Care was taken to ensure that each patient lied on the back with their patellae facing upward, to minimize rotational variation among the radiographs. At the same time, 30 patients with simple meniscus injury who underwent arthroscopy during the same period were selected to determine the degree of tibiofemoral coronal subluxation as the baseline value. The changes before and after operation were compared, as well as the differences with the baseline data.ResultThe average follow-up period was 21.2 ± 5.8 months. The average distance of tibial coronal subluxation before ACLR was 5.5 ± 2.1 mm, which was significantly different from that of baseline group (7.3 ± 2.1 mm) (P < 0.001). The tibial subluxation after ACLR was 7.7 ± 2.6 mm, which was significantly different from that before operation (P < 0.001). There was no significant difference in the distance between postoperative tibial subluxation and baseline group (P = 0.472).ConclusionThe tibia was coronally medially subluxated after ACL rupture. ACLR can correct the medial subluxation of tibia. This finding is helpful in the diagnosis of ACL rupture, and can be used to assess the imaging status of the tibiofemoral joint on the coronal plane during or after ACLR.

Three-dimensional motion of the patella in French bulldogs with and without medial patellar luxation

BackgroundFrench bulldogs exhibit significantly larger femoral external rotation and abduction than other breeds. We were curious as to whether this peculiar leg kinematic affects patellar motion and/or might induce medial patellar subluxation (MPSL) or medial patellar permanent luxation (MPPL). We hypothesized that the more abducted leg posture during stance causes an unusual medial pull direction of the rectus femoris muscle during stance, and that this may facilitate the occurrence of MPSL or even MPPL during locomotion. To test our hypothesis, we analyzed existing stifle-joint X-ray-sequences collected during the treadmill walk and trot of seven adult female French bulldogs. We estimated 3D-patellar kinematics using Scientific Rotoscoping.ResultsThe three-dimensional motion of the patella comprises rotations and translations. From the seven dogs analyzed, three exhibited MPSL and one MPPL during the gait cycle. Medial patellar luxation (MPL) occurred mostly around toe-off in both gaits studied.Patellar position was generally not gait-related at the analyzed timepoints. In dogs with MPL, the patella was placed significantly more distally (p = 0.037) at touch-down (TD) and at midswing (p = 0.024), and significantly more medial at midswing (p = 0.045) compared to dogs without MPL.ConclusionsMedial patellar luxation seems to be the consequence of the far from parasagittal position of the stifle joint during stance due to a broad trunk, and a wide pelvis. This peculiar leg orientation leads to a medial sideway pull caused by the rectus femoris muscle and the quadriceps femoris and may initiate plastic deformation of the growing femur and tibia. Thus, a way to avoid MPL could be to control breeding by selecting dogs with lean bodies and narrow pelvis. Actual breeding control programs based on the orthopedic examination are susceptible to errors. Systematic errors arise from the fact that the grading system is highly dependent on the dog’s condition and the veterinarians’ ability to perform the palpation on the stifle. Based on our results, the position of the patella at TD, or even perhaps during stand might offer a possibility of an objective radioscopic diagnostic of the MPL.

Closing wedge ostectomy with transfixation pin-cast stabilization for correction of angular limb deformities of the metatarsophalangeal region in four cattle.

4 calves were evaluated because of lameness and an angular limb deformity of the metatarsophalangeal region. 3 calves (ages, 5 days, 10 days, and 1 month) had a congenital varus deformity of the metatarsophalangeal region characterized by medial subluxation of the first phalanx of digits 3 and 4 at the metatarsophalangeal joints. A 6-month-old heifer had a valgus deformity of the metatarsophalangeal region secondary to a malunion of a Salter-Harris type II fracture. The degree of deformity angulation ranged from 16° to 54° for the 4 patients. A closing wedge ostectomy with transfixation pin-cast application was performed on the affected limb of all 4 patients. The ostectomy healed with only minor complications (disuse osteopenia distal to the transfixation pins [n = 4] and cast sores [1]) that were easily resolved with no long-term adverse effects. Duration of follow-up for the 4 patients ranged from 6 to 17 months, and the owners reported satisfactory ambulation with no (n = 2) or only mild (2) residual lameness in the affected limb. Results suggested that a closing wedge ostectomy with transfixation pin-cast stabilization is an alternative for management of angular limb deformities of the metatarsophalangeal region in cattle. Such treatment improved the quality of life for all 4 patients. However, 2 of the 4 patients had congenital deformities confirmed to be heritable. There are ethical concerns associated with treating animals with heritable disorders, and exhibition and breeding of such animals should be avoided.

Medial Subluxation or Dislocation of the Biceps on Magnetic Resonance Arthrography Is Reliably Correlated with Concurrent Subscapularis Full-Thickness Tears Confirmed Arthroscopically

Background The purpose of this study was to investigate the relationship between biceps medial subluxation/dislocation on the magnetic resonance arthrography (MRA) imaging and subscapularis full-thickness tear confirmed arthroscopically. We hypothesized that presence of a biceps medial subluxation or dislocation would strongly indicate a subscapularis full-thickness tear. Methods A total of 432 consecutive patients who underwent arthroscopic repair for rotator cuff tears with/without subscapularis tears at our institute were retrospectively reviewed. The inclusion criterion of this study was preoperative MRA images taken within 6 months of arthroscopic repair. The presence of medial subluxation/dislocation was evaluated on the preoperative MRA images, and subscapularis tear was confirmed on arthroscopic examination. Results Biceps subluxation/dislocation was identified in 46 of the 432 patients on MRA. Forty-five of these 46 patients also had a subscapularis full-thickness tear identified in arthroscopic examination. Among the 386 patients who did not have biceps subluxation or dislocation, 54 patients had a subscapularis full-thickness tear diagnosed arthroscopically. The presence of a biceps subluxation/dislocation could predict a subscapularis full-thickness tear with sensitivity of 45% (45/99), specificity of 99% (332/333), positive predictive value of 98% (45/46), negative predictive value of 86% (332/386), and accuracy of 87% (377(45 +332)/432). Conclusion Medial subluxation/dislocation of the biceps on MRA images was highly associated with a concurrent subscapularis full-thickness tear which was confirmed arthroscopically. This association had 99% specificity and 98% positive predictive value. Therefore, if a biceps subluxation/dislocation is identified on MRA images, there is a high chance that a concurrent subscapularis full-thickness tear exists.

Coronal tibiofemoral subluxation is correlated to correction angle in medial opening wedge high tibial osteotomy.

This study aimed to analyse the change in coronal tibiofemoral (CTF) subluxation after high tibial osteotomy and to determine demographic variables associated with CTF subluxation. The change in CTF subluxation was hypothesised to be associated with the magnitude of correction of lower limb alignment and medial proximal tibial angle (MPTA). A total of 103 consecutive knees in 86 patients who underwent medial opening wedge high tibial osteotomy for symptomatic medial compartment knee osteoarthritis were retrospectively analysed. The normal %CTF subluxation value, which was defined as a subluxation of the proximal tibia relative to the distal femur on the lateral edge of the femorotibial joint, was determined from 60 normal knees. The association between CTF subluxation and the Knee Society Score (KSS) and radiographic parameters was examined. The normal range for %CTF subluxation was defined as - 1.8 to 5.6%. Following osteotomy, Δ%CTF subluxation reduced from a mean of 4.5% (- 12.1 to - 4.6%) to 0.7% (- 6.8 to 8.2%), resulting in a decrease in lateral tibiofemoral subluxations concomitant with an increase in medial subluxations. The reduction in CTF subluxation correlated moderately with MPTA change (r = - 0.454, p < 0.001) and weakly with preoperative lower limb alignment as represented by hip-knee-ankle angle and %weight-bearing line. Multivariate regression analysis showed that ΔMPTA was a significant contributor of Δ%CTF subluxation. Osteotomy reduced CTF subluxation, which was correlated with MPTA change. Postoperative MPTA should be considered during surgical planning, and a postoperative MPTA of approximately 93.5° may be an appropriate target to reduce CTF subluxation by obtaining normal CTF congruency. Level IV therapeutic, retrospective, cohort study.

Lateral patellar retinacular release: changes over the last ten years

Lateral retinacular release is a useful resource in knee surgery that can be used for disorders of the extensor mechanism. For many years, it was indiscriminately used in the treatment of the various patellofemoral joint alterations, with conflicting functional results. This study aimed to analyze the changes that have occurred in the indications and clinical effectiveness of lateral retinacular release by reviewing the relevant literature of the past ten years, comparing it to the classic literature on the subject. It was found that less extensive releases decompress the lateral patellar facet, helping with pain control, while decreasing the risks of medial subluxation. Nowadays, there is clear evidence for its indication in the lateral patellar hypercompression syndrome associated with anterior knee pain, as long as there is no related instability; furthermore, it will normally play an adjuvant role in extensor mechanism alignment surgeries for cases of recurrent patellar instability. The initial results for symptomatic patellofemoral osteoarthritis are promising when lateral release is combined with cartilage debridement; in total knee replacement, it is more commonly used for the correction of valgus deformity in order to improve the components’ congruency. Finally, distinguishing the different patellofemoral joint pathologies is seen as crucial in order to indicate this procedure. Further randomized control trials that compare surgical techniques with long-term results are still needed.

Correction of Tibial Valgus Deformity.

AbstractValgus tibial malalignment may be the result of bony deformity, previous lateral meniscectomy, or lateral plateau fractures. The correction of such a problem is usually addressed through a tibial osteotomy, which affects the alignment both in flexion and extension. Two surgical options are available: medial closing wedge and lateral opening wedge. When planning a varisation osteotomy, it should be considered that the normal joint line is in 3 degrees of varus. Increasing this obliquity beyond 10 to 15 degrees ends up with increased loads on the patellofemoral joint and medial subluxation of the femur on the tibia. The aim of the present study was to discuss actual indications and contraindications for a varus-producing high tibial osteotomy and describe surgical steps of both medial closing wedge and lateral opening wedge techniques. In addition, the available literature has been searched to report functional outcomes and complications.

Medial Patella Subluxation after Minor Trauma

Most cases of medial patella subluxation occur under iatrogenic conditions that are often associated with a prior excessive lateral retinacular release procedure. We report a case of medial subluxation following minor trauma with no history of previous lateral release. The abnormality was identified on magnetic resonance imaging and was successfully treated by direct repair of the lateral retinaculum. The recognition and treatment of medial subluxation of the patella without retinacular release can be difficult. Therefore, consideration of multiple causes through careful medical history taking, physical examination, and radiologic examination is needed for accurate diagnosis.

Secure Screw Placement in Management of Acetabular Fractures Using the Suprapectineal Quadrilateral Buttress Plate.

Acetabular fractures involving predominantly the anterior column associated with a disruption of the quadrilateral surface can be treated with instrumentation implementing the stabilization of the quadrilateral surface. The recently introduced suprapectineal quadrilateral buttress plate is specifically designed to prevent secondary medial subluxation of the femoral head, especially in elderly patients with reduced ability for partial weight bearing. Whereas there are guidelines available for safe screw fixation for the anterior and posterior columns, there might be a concern for intra-articular placement of screws placed through the infrapectineal part of the quadrilateral buttress plate. Within this report we analyzed retrospectively screw placement in 30 plates in postoperative CT scans using algorithms for metal artifact reduction. None of the screws of the buttress plate penetrated the hip joint. We describe the placement, length, and spatial orientation of the screws used for fracture fixation and suggest that the use of intraoperative image intensifiers with a combined inlet-obturator view of 30–45° best projects the screws and the hip joint. Preoperative knowledge of approximate screw placement and information for accurate intraoperative imaging may contribute to safe acetabular fracture fixation and may reduce operating time and limit radiation exposure to the patient and the personnel. This trial is registered with KEK-BE: 266/2014.

Liberação retinacular lateral da patela: o que mudou nos últimos dez anos

Lateral retinacular release is a useful resource in knee surgery that can be used for disorders of the extensor mechanism. For many years, it was indiscriminately used in the treatment of the various patellofemoral joint alterations, with conflicting functional results. This study aimed to analyze the changes that have occurred in the indications and clinical effectiveness of lateral retinacular release by reviewing the relevant literature of the past ten years, comparing it to the classic literature on the subject. It was found that less extensive releases decompress the lateral patellar facet, helping with pain control, while decreasing the risks of medial subluxation. Nowadays, there is clear evidence for its indication in the lateral patellar hypercompression syndrome associated with anterior knee pain, as long as there is no related instability; furthermore, it will normally play an adjuvant role in extensor mechanism alignment surgeries for cases of recurrent patellar instability. The initial results for symptomatic patellofemoral osteoarthritis are promising when lateral release is combined with cartilage debridement; in total knee replacement, it is more commonly used for the correction of valgus deformity in order to improve the components’ congruency. Finally, distinguishing the different patellofemoral joint pathologies is seen as crucial in order to indicate this procedure. Further randomized control trials that compare surgical techniques with long‐term results are still needed.

Medial Subluxation of the Tibia After Anterior Cruciate Ligament Rupture as Revealed by Standing Radiographs and Comparison With a Cadaveric Model

Background: Biomechanical studies indicate that the tibia shifts medially and has a more valgus orientation in the anterior cruciate ligament (ACL)–deficient knee. However, it is not known whether these differences can be detected on standing radiographs. Purpose: To determine whether medial subluxation and more changes in coronal alignment of the tibia are detectable in both weightbearing radiographs and a cadaveric model simulating quiet standing. Study Design: Case series; Level of evidence, 4, and Descriptive laboratory study. Methods: Radiographic data were available for a cross-section of 74 patients with unilateral ACL tears. Tibial subluxation and coronal limb alignment were measured on hip-to-ankle weightbearing radiographs. Eight cadaveric knees were mounted on a 6 degree of freedom robot. Mediolateral position and varus-valgus alignment of the tibia relative to the femur were measured in response to 300-N axial compression simulating quiet standing at 5° and 15° of flexion with the ACL intact and sectioned. Results: Across all 74 patients included in the clinical study, the ACL-injured knee experienced 1.6 ± 2.3 mm (mean ± SD) of medial tibial subluxation compared with the contralateral uninjured knee (P < .001). The 24 patients with isolated ACL rupture exhibited 2.0 ± 1.8 mm of medial subluxation (P < .001). The mean coronal alignment of all 74 patients in the study was 0.7° ± 2.8° varus in the injured limb and 1.3° ± 2.6° varus in the uninjured contralateral limb (P = .0187). In the cadaveric model, the tibia translated 0.4 ± 0.5 mm more medially after sectioning of the ACL at 15° of flexion (P = .0485); however, no changes in coronal alignment were detected. Conclusion: The tibia shifts medially and is less varus in the ACL-deficient knee on standing radiographs. The medial tibial shift is reproduced in an axially loaded cadaveric model. Clinical Relevance: Medial tibiofemoral subluxation seen on frontal plane standing radiograph is an underappreciated sequela of isolated ACL rupture. The ability of ACL reconstruction to restore this aspect of ACL injury is not well understood and should be investigated further. Cadaveric models may be used to directly measure the mechanical effect of subtle changes in mediolateral position on articular contact stress as an indicator of the importance of this finding.

A Retrospective Study of 63 Hallux Valgus Corrections Using the Osteodesis Procedure

Osteotomy procedures have been the most popular approach to hallux valgus deformity correction. Soft tissue approaches have, in general, been regarded as ineffective for moderate and severe hallux valgus deformities. Osteodesis is a soft tissue technique that has been shown to be effective in the past but is still seldom practiced. In the present report, we describe a retrospective study of 63 hallux valgus feet in 36 patients who had undergone the osteodesis procedure. Their mean age was 46 ± 12 years, and the mean follow-up period was 25.4 ± 9.6 months. The surgical technique consisted of metatarsus primus varus deformity correction by intermetatarsal cerclage sutures and hallux valgus deformity correction by rebalancing the ligaments. The first metatarsophalangeal angle improved from a mean of 32.5° ± 7.6° preoperatively to 18.4° ± 7° postoperatively, the first intermetatarsal angle improved from 14.6° ± 2.6° to 6.8° ± 1.8°, and the American Orthopaedic Foot and Ankle Society score improved from 59 ± 14 to 93 ± 8 points. The rate of patient satisfaction after surgery was 92% (33 of 36 patients, 59 of 63 feet). The complications included a second metatarsal stress fracture in 3 feet (5%), metatarsophalangeal joint medial subluxation in 3 feet (5%), and metatarsophalangeal joint stiffness in 5 feet (8%). This soft tissue, nonosteotomy procedure was a safe technique that effectively corrected hallux valgus and metatarsus primus varus deformities of various severities without osteotomy or fusion.

Quantitative ultrasound facilitates the exploration of morphological association of the long head biceps tendon with supraspinatus tendon full thickness tear.

BackgroundsPathology of the long head biceps tendon (LHBT) is associated with rotator cuff tears but whether the LHBT texture changes following supraspinatus tendon full thickness tear (SSFT) can be detected at the extra-articular segment remains unknown. This cross-sectional study aimed to explore the morphological differences of the LHBT in shoulders with and without deficient rotator cuffs by using quantitative ultrasound.Materials and MethodsWe selected 145 cases with SSFT and 145 age-and- gender-matched controls. The width, thickness, flattening ratio, cross-sectional area, and echogenicity ratio of the LHBT were measured and a general linear model was used to clarify the relationship between rotator cuff pathology and LHBT morphology. The receiver operating characteristic curves of each parameter were constructed for SSFT discrimination and the maximal Youden indexes were used to define the best cut-off points.ResultsWe found increased thickness and cross-sectional area but decreased flattening ratio in shoulders with SSFT, and no between-group differences in the width and echogenicity ratio. The LHBT appearance was modified by biceps peritendinous effusion and medial subluxation, but not by the size of SSFT. The flattening ratio was the best discriminator for SSFT with an area under curve of 0.81 (95% confidence interval, 0.76–0.86). The cut-off values to differentiate between the non-tear and tear groups were 2.00 mm of the thickness, 1.73 of the flattening ratio and 10.53 mm2 of the cross-sectional area.ConclusionQuantitative ultrasound facilitated the detection of the LHBT morphological changes following SSFT and demonstrated its potential utility in discriminating rotator cuff deficiency.