Tibial Allograft Research Articles

Fixation Type Does not Affect the Learning Curve and Short-Term Radiographic Outcomes for Arthroscopic Anatomic Glenoid Reconstruction with Distal Tibia Allograft

PurposeThe purpose of this study was to compare the learning curves and radiographic variables between screw and suture button fixation of the allograft for surgeons learning the all-arthroscopic anatomic glenoid reconstruction (AAGR) technique for anterior shoulder instability. We compared the surgical times of these two fixation techniques, as well as the graft placement in the vertical and medial-lateral directions.MethodsThis was a retrospective review of patients who underwent AAGR for recurrent anterior shoulder instability. Start and end times were recorded for each procedure, and learning was assessed through the change in operative time over successive surgeries and by variability of operative time. Graft placement, in terms of vertical positioning, medial-lateral step formation, and obliquity of fixation (alpha angle), was evaluated using 3-dimensional CT scans at approximately 6 months postoperation.ResultsA total of 43 patients were included in our study. Twenty-seven had screw fixation, and 16 had suture button fixation. The surgical duration of the button fixation technique was comparable to that of screw fixation (P = .72), with no significant difference in the variability of surgical time in either cohort (P > .05). Both groups showed similarly optimal vertical positioning of the graft onto the lower third of the glenoid (P = .89). Desired obliquity of graft fixation was identified more frequently with button fixation (P < .001). Both fixation methods provided clinically acceptable medial-lateral step formations, with suture-button fixation being significantly larger (P = .03).ConclusionsSuture button fixation of the allograft is a potential alternative to screw fixation for the management of glenoid bone loss in recurrent anterior shoulder instability. The results of this study show that this method has a comparable learning curve, with a similar surgical duration, while not compromising the optimal accuracy of vertical and medial-lateral placement of the graft and achieves a superior alpha angle of fixation.Level of EvidenceLevel III, retrospective cohort study.

Open Posterior Glenoid Reconstruction Using a Distal Tibial Allograft

Background: Posterior instability is less common than anterior instability but can be seen in contact athletes and posttraumatically. Distal tibial allograft reconstruction for glenoid bone loss was first described by Provencher and colleagues in 2009 and an arthroscopic technique for posterior glenoid reconstruction using a distal tibial allograft was later described by Gupta et al in 2013. Indications: The primary indications for posterior distal tibial allograft include the failure of conservative management, recurrent instability after an arthroscopic stabilization, or glenoid bone loss &gt; 20% to 25%. Technique Description: The patient is positioned in lateral decubitus, and examination under anesthesia is performed. Following arthroscopic evaluation, an incision is made medial to the posterolateral aspect of the acromion at the glenohumeral joint level. Electrocautery is carried to the deltoid, which is split in line with its fibers. A split between the infraspinatus and teres minor is performed. Vertical capsulotomy is performed, and deep retractors are placed. Attention is turned to the back table for graft preparation. The graft is measured, marked on the lateral aspect of the articular surface, and cut accordingly. Two 3.5-mm holes are drilled 1 cm apart, and the graft is thoroughly irrigated before being placed into the wound. A 2.5-mm drill is used in the 3.5-mm holes, and two 3.5-mm solid fully threaded screws are placed under power and tightened by hand. The wound is closed in the traditional fashion. Results: Graft nonunion and/or resorption are the primary concerns following posterior distal tibial allograft. Amar et al found no cases of nonunion or partial unions on 6-month computerized tomography (CT) scan, most patients having no or &lt;50% resorption. Millet et al also found bony union by CT scan and improved patient-reported outcome measures. A case series by Gilat et al found 90% of patients reported restoration of stability. Discussion/Conclusion: Posterior distal tibial allograft is a successful surgical intervention for patients with recurrent posterior shoulder instability with glenoid bone loss.

Anterior Glenoid Reconstruction With Distal Tibial Allograft: Biomechanical Impact of Fixation and Presence of a Retained Lateral Cortex.

Background:Glenoid reconstruction with distal tibial allograft (DTA) is a known surgical option for treating recurrent glenohumeral instability with anterior glenoid bone loss; however, biomechanical analysis has yet to determine how graft variability and fixation options alter the torque of screw insertion and load to failure.Hypothesis:It was hypothesized that retention of the lateral cortex of the DTA graft and the presence of a washer with the screw will significantly increase the maximum screw placement torque as well as the load to failure.Study Design:Controlled laboratory study.Methods:Whole, fresh distal tibias were used to harvest 28 DTA grafts, half of which had the lateral cortex removed and half of which had the lateral cortex intact. The grafts were secured to polyurethane solid foam blocks with a 2-mm epoxy laminate to simulate a glenoid with an intact posterior glenoid cortex. Grafts underwent fixation with 4.0-mm cannulated drills, and screws and washers were used for half of each group of grafts while screws alone were used for the other half, creating 4 equal groups of 7 samples each. A digital torque-measuring screwdriver recorded peak torque for screw insertion. Constructs were then tested in compression with a uniaxial materials testing system and loaded in displacement control at 100 mm/min until at least 3 mm of displacement occurred. Ultimate load was defined as the load sustained at clinical failure.Results:The use of a washer significantly improved the ultimate torque that could be applied to the screws (+cortex and +washer = 12.42 N·m [SE, 0.82]; –cortex and +washer = 10.54 N·m [SE, 0.59]) (P < .0001), whereas the presence of the native bone cortex did not have a significant effect (+cortex and –washer = 7.83 N·m [SE, 0.40]; –cortex and –washer = 8.03 N·m [SE, 0.56]) (P = .181).Conclusion:In a hybrid construct of fresh cadaveric DTA grafts secured to a foam block glenoid model, the addition of washers was more effective than the retention of the lateral distal tibial cortex for both load to failure and peak torque during screw insertion.Clinical Relevance:This biomechanical study is relevant to the surgeon when choosing a graft and selecting fixation options during glenoid reconstruction with a DTA graft.

Multilevel Lumbar En-bloc Vertebrectomy for Chordoma

Objective: To demonstrate that total en bloc removal of chordoma involving multiple vertebrae of the lumbar spine is achievable, using a technique previously described for single level tumors. It is a technically demanding procedure which requires careful planning. We also show that femoral or tibial allograft provides a strong and cheaper alternative to modern cages and should be considered for anterior reconstruction in these cases. Methods: We describe in detail the technique used in a patient who presented with a lumbar chordoma extending over three vertebral bodies, L3 to L5, which in addition had expanded bilaterally into the paravertebral region. The initial reconstruction failed as the intervertebral cage dislocated. We revised this with tibial allograft and obtained a solid construct this way. Results: Complete en bloc excision and stable reconstruction was ultimately achieved despite the difficulties we encountered. At five years the patient remained disease free. Conclusions: En bloc resection of chordoma involving multiple lumbar vertebrae is feasible. The technique described may be used for other tumors involving the lumbar spine, perhaps even in cases where more than three levels are involved. Tibial or femoral allograft provides a better and cheaper alternative to cages and can be useful when resources are scarce.

Treatment of Failed Latarjet With Arthroscopic Anatomic Glenoid Reconstruction

PurposeVarious methods have been described for the treatment of anterior shoulder instability with glenoid bone loss. The incidence of recurrent dislocations following surgical intervention is high and, therefore, necessitates a reliable and replicable revision procedure. The purpose of this Technical Note is to describe a method of arthroscopic anatomic glenoid reconstruction using a distal tibial allograft and screw fixation in the setting of a failed Latarjet procedure with significant glenoid bone loss.MethodsWe describe in detail patient positioning, portal placement, steps of the diagnostic arthroscopy, and graft preparation using imaging and a detailed intraoperative arthroscopic technique.Level of EvidenceLevel 1, Shoulder; Level 2, Instability.

Arthroscopic Distal Tibial Allograft for Posterior Glenoid Reconstruction

Background: Posterior glenoid bone loss occurs in more than two-thirds of patients with posterior glenohumeral instability, with 14% to 22% having greater than subcritical bone loss (13.5%), a marker for potential need for bony augmentation versus soft tissue-only procedures. Several techniques are described to augment either the version or volume of the glenoid surface including osteotomies, autograft transfers, and allograft tibia transfers. Indications: Arthroscopic-assisted allograft distal tibia bone block augmentation to the posterior glenoid is indicated for revision posterior instability procedures with posterior bone loss and in primary cases of posterior instability with critical bone loss. Technique Description: Arthroscopic posterior glenoid reconstruction with allograft distal tibia and posterior labral repair in the lateral position is presented. This technique uses standard instrument sets and requires no patient repositioning. The preplanned tibial bone block is prepared on a back table either prior to, or concurrently with, arthroscopic procedure. After creation of high posterior portal and standard anterior portal, a sucker-shaver and burr are used to create a perpendicular edge for apposition of the allograft tibia. The bone block is introduced through a longitudinal incision and underdelivered to the prepared surface under the liberated labrum. The articular surface of the graft and glenoid are aligned and cannulated screws are used to compress the bone block against the native glenoid. The posterior labral tissue is then mobilized over the graft and repaired to the native glenoid. Results: Arthroscopic distal tibial allograft augmentation for posterior bone loss restored stability and function in a small cohort of patients. Patients reported improved stability in the immediate postoperative course, with restoration of motion by 2 months. Push-ups, pull-ups, and return to full active duty without restrictions is allowed at 6 months postoperatively. Imaging at 3 months postoperatively has shown excellent graft healing. Discussion: The benefits of allograft tibia augmentation for posterior instability with glenoid bone loss include an anatomic joint surface restoration including articular cartilage, lack of donor site morbidity, and a minimally invasive approach. When performed arthroscopically, this technique permits concurrent posterior labral repair and anatomic reconstruction.

Posterior Glenoid Reconstruction Using a Distal Tibial Allograft

Posterior shoulder instability is increasingly recognized and diagnosed in young athletes. These patients often present with vague shoulder pain rather than the frank instability commonly seen with anterior instability. Three common causes of posterior shoulder instability are congenital retroversion, a single traumatic event, or repetitive microtrauma with erosive effects. The critical determination when deciding on the appropriate treatment of posterior shoulder instability is the presence and degree of glenoid bone loss. In patients without bone loss, arthroscopic procedures have a high success rate with a failure rate of less than 10% and an 89% return-to-sport rate. The determination of the critical amount of bone loss that would permit an arthroscopic procedure is controversial, but recent reports that attempt to quantify the critical bone loss value posteriorly have ranged from 13.5% to 20%. This Technical Note describes our preferred method of open surgical treatment of posterior shoulder instability with posterior glenoid bone loss using an intra-articular distal tibial allograft.

Arthroscopic Glenoid Reconstruction With Iliac Crest Bone Block Transfer in the Beach Chair Position

Large anterior glenoid defects pose significant challenges for shoulder stability. Arthroscopic glenoid reconstruction techniques using distal tibia allograft have been proposed as alternatives to open or arthroscopic Latarjet procedures but can increase operating room costs. Iliac crest bone block autograft is a cost-effective option without concern for the graft being undersized. Previous techniques have described arthroscopic glenoid reconstruction in the lateral position, but the beach chair position provides ease of access to both the iliac crest bone graft harvest and arthroscopic bone transfer, as well as facilitates possible conversion to an open approach if necessary. We present our surgical technique for performing an arthroscopic glenoid reconstruction with iliac crest autograft bone block transfer in the beach chair position.

Donor-Specific Human Leukocyte Antigen Antibody Formation After Allograft Glenoid Reconstruction Occurs But Does Not Impact Clinicoradiographic Outcomes

Background: Recurrent shoulder instability is a prevalent condition, with glenoid bone loss as a common cause. Arthroscopic repair using distal tibial allografts provides long-lasting treatment by restoring glenoid surface area and presumably avoids risks of sensitization against donor human leukocyte antigen (HLA). Two case studies have challenged this assumption, suggesting that small bone allografts are able to induce host adaptive immune responses to donor HLA. The incidence of small bone allograft HLA sensitization and its effects on resorption and patient outcomes are unclear. Purpose/Hypothesis: The purpose was to assess the rate of sensitization against donor HLA after distal tibial allograft procedures for shoulder instability due to glenoid bone loss and to find whether HLA sensitization negatively affects patient-reported and radiographic outcomes. We hypothesized that sensitized patients would have worse radiographic and self-reported outcomes compared with nonsensitized patients. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 71 patients with a mean age of 28.85 years (range, 13.58-61.31 years) were enrolled, with 58 patients submitting sufficient pre- and postoperative blood samples for HLA antibody testing. In patients who developed HLA antibodies postoperatively, donor HLA typing was used to confirm donor-specific sensitization. Pre- and postoperative computerized tomography scans (0.9 ± 0.8 years follow-up) were used to grade resorption based on the modified Zhu resorption grade classification (ie, grade 0 = no resorption; grade 1 = less than 25% resorption; grade 2 = between 25% and 50% resorption; and grade 3 = larger than 50% resorption). The Western Ontario Shoulder Instability Index outcome scores were obtained preoperatively and at regular postoperative appointments. Resorption and outcome data were compared between sensitized and nonsensitized patients using the Fisher exact test, independent 2-tailed Student t tests, and the Wilcoxon rank-sum test to determine the effect of HLA sensitization on radiographic and patient-reported outcomes. Results: A total of 7 (12.1%) patients with sufficient HLA samples were sensitized against donor HLA postoperatively. Sensitized patients did not have significantly higher rates of resorption (21.9% vs 14.3%, 21.9% vs 28.6%, 43.8% vs 28.6%, and 12.5% vs 28.6% for respective resorption grades 0-3; P = .67; α = .05). Self-reported outcomes were not statistically significant between sensitized and nonsensitized patients (24.9 ± 27.61 vs 40.16 ± 18.99; P = .37; α = .05) and did not differ significantly based on resorption grade (47.4 ± 0.0 vs 55.2 ± 18.8, 30.4 ± 15.8 vs 39.9 ± 20.9, 41.2 ± 0.0 vs 39.1 ± 13.1, and -24.9 ± 0 vs 24.4 ± 19.6 for resorption grades 0-3; P > .05; α = .05). Conclusion: Sensitization against donor HLA after small bone graft allografting was not previously considered but has been brought to light as a possibility. Aside from potential complications for future organ transplants, HLA sensitization does not introduce a risk for adverse outcomes or higher grades of resorption compared with nonsensitized patients after small bone allografting for shoulder instability.

Arthroscopic Distal Clavicle Glenoid Augmentation: Rationale and Surgical Technique

Glenoid bone loss remains an important determinant of outcome in the surgical management of anterior shoulder instability. Multiple options are available to address this bone loss including autograft bone transfers, such as coracoid or iliac crest grafts. Allograft options include both bone and osteochondral options, such as the distal tibial allograft. Each of these choices has potential advantages and disadvantages. An ideal approach would provide an autograft source of osteochondral material that is well-matched to the defect, readily available, cost effective, and with minimal morbidity. In this article, we present the distal clavicle autograft as an ideal option for consideration in the treatment of glenoid bone loss. The graft has a cortical and cancellous side for direct fixation and is amenable to arthroscopic techniques using standard portals and obviating the need to go near the neurovascular structures of the shoulder. Recent work has demonstrated the utility of this graft in providing an anatomic restoration of the glenoid articular surface with a cartilage cap comparable in thickness to that of the native glenoid. Along with a summary of the pertinent literature, this article outlines the rationale, indications, and technical evolution for this procedure.

Distal Tibial Plafond Allograft Transplant for Anterior Shoulder Instability

Anterior shoulder instability is a relatively common condition particularly in the athletic population. It can lead to alterations in shoulder mechanics that can cause significant restrictions for patients. This condition becomes particularly difficult to treat in the revision setting. A handful of widely accepted procedures to address anterior shoulder instability have been described. Distal tibial allograft for anterior shoulder instability in the setting of large glenoid loss and revision cases has been shown to be on par with other graft types. In this chapter we will discuss a technique of distal tibia allograft use for anterior shoulder instability cases.

Arthroscopic Distal Tibial Allograft Reconstruction for Anterior Shoulder Instability

Arthroscopic distal tibial allograft (DTA) reconstruction has recently gained attention for treatment of anterior shoulder instability. Glenoid grafting using the DTA confers more anatomic glenoid reconstruction and recent studies have shown good clinical outcomes similar to the Latarjet procedure, and with negligible complication rates. Patient profile and glenoid assessment using computed tomography (CT) reconstruction images are most important in selecting eligible patients. The inherent advantages of anatomic arthroscopic glenoid reconstruction (AAGR) are: the safety profile of this technique, the quick learning curve, the preservation of subscapularis anatomy and the absence of donor site morbidity. There are no major adverse events reported with arthroscopic DTA. However, graft availability and cost remain a limitation to this graft option. The current chapter describes the surgical technique for AAGR using a distal tibia allograft.

Treatment Algorithm for Recurrent Anterior Shoulder Instability: Putting It All Together

Our understanding of recurrent anterior shoulder instability has increased over the past decade. Treatment is a challenging dilemma for the treating surgeon, especially in young athletes. Recurrent dislocation rates after nonoperative management of first-time dislocations in young athletic patients remains high, and many patients ultimately require operative intervention. A thorough history and physical exam is essential to evaluate concomitant pathology and risk factors for failure of nonoperative and operative treatment. Once surgical intervention is warranted, imaging modalities including radiographs, computed tomography, and magnetic resonance imaging are important for surgical planning to evaluate the extent of the tear, quality of the tissue and surrounding capsule, identifying concomitant pathology, and evaluating bone stock of the glenoid and humerus. Various surgical options exist, including arthroscopic Bankart repair, open Bankart repair, and bony augmentation procedures such as Latarjet, Bristow, and distal tibia allograft. Postoperative rehabilitation is crucial to success and should be performed with a systematic approach with ultimate return to play testing before allowing an athlete to return to sport. This review discusses the presentation, diagnosis, and treatment algorithm for recurrent anterior shoulder instability.

State of the art for treatment of bony defects around anterior shoulder instability—the American perspective

AbstractWhile arthroscopic Bankart repair yields high success rates, bone loss on the glenoid or humeral head can portend a poor outcome. The authors recommend a thorough evaluation including computed tomography (CT) scanning to best evaluate the amount of bone loss. Multiple studies have shown that the outcomes of revision stabilization procedures are inferior to the respective primary procedure; thus, it is of paramount importance to select the correct index procedure to optimize patient outcome. The authors present the American perspective on treating shoulder instability. For patients with a small on-track Hill Sachs lesion and less than 10 % glenoid bone loss, an isolated arthroscopic Bankart repair is appropriate. This procedure is also recommended for bony Bankart lesions, as well as in overhead throwing athletes. With an engaging Hill Sachs lesion and less than 15 % glenoid bone loss, the authors recommend the addition of a remplissage to the arthroscopic Bankart repair. For patients with up to 15 % bone loss or following a failed previous arthroscopic repair, the authors advocate for open Bankart repair. They recommend Latarjet in patients with a non-engaging Hill Sachs lesion greater than 15 % bone loss. Patients with bone loss over 30 % would benefit from bone grafting with iliac crest autograft or distal tibia allograft for stabilization. In summary, the authors believe that the index procedure provides an opportunity to optimize patient outcome and careful consideration of the treatment options is warranted.

Arthroscopic Posterior Glenoid Reconstruction Using a Fresh Distal Tibia Allograft for Recurrent Posterior Instability

Posterior glenohumeral instability is a relatively uncommon cause of shoulder instability. Recurrent posterior instability with static posterior humeral head subluxation is often associated with critical glenoid bone loss. Unlike anterior instability, the amount of bone loss for posterior instability that requires surgical reconstruction remains a topic of debate. Several techniques have been described to treat critical bony defects in patients with recurrent posterior shoulder instability with the use of both autografts and allografts depending on the amount of bone loss present. Open posterior glenoid bone block procedure is associated with increased risk of complications and morbidity to the patient. As such, all-arthroscopic techniques have emerged with the advantage of allowing for the diagnosis and treatment of concomitant glenohumeral pathology and minimizing soft-tissue dissection through the posterior deltoid and rotator cuff muscles. Reported short-term outcomes of arthroscopic posterior bone block stabilization are promising; however, it remains a technically challenging procedure due to intra-articular graft insertion and subsequent fixation congruent to the posterior glenoid articular margin. We describe an all-arthroscopic technique using a fresh distal tibia allograft fixation using 2 partially threaded screws in conjunction with an arthroscopic Latarjet fixation set for a patient with recurrent posterior shoulder instability and associated glenoid bone loss.

Complex Revision Glenoid Reconstruction with Use of a Distal Tibial Allograft.

Coracoid transfer procedures have been increasingly utilized for anterior shoulder instability with associated glenoid bone loss1. Unfortunately, in a young, high-risk patient population, these procedures can fail secondary to traumatic causes but also because of bone graft resorption or malposition or hardware prominence, among other reasons2. In active patients, revision glenoid reconstruction may be indicated. Distal tibial osteoarticular allografts have been utilized to treat recurrent anterior shoulder instability for several years3. Recently, this technique has been applied to cases of failed Latarjet procedures in order to reconstitute the absent glenoid bone stock4, demonstrating excellent clinical outcomes at a minimum follow-up of 3 years2. The procedure is performed in the beach-chair position. First, a diagnostic shoulder arthroscopy is performed to assess the cartilaginous surfaces, to examine the Hill-Sachs lesion and its engagement, and to remove any loose bodies. Next, the prior deltopectoral incision is developed, and the deltopectoral interval is utilized to visualize the subscapularis. The subscapularis is split at the junction of its upper two-thirds and lower one-third. Careful dissection is used to develop the subscapularis split from lateral to medial because the prior coracoid transfer affects the native neurovascular anatomy medially. If substantial coracoid bone remains from the previous transfer, a conjoined tendon tenotomy can be performed to further aid in visualization5. Next, any associated hardware is removed, and the coracoid bone remnant is removed. The glenoid defect is sized, and the osseous glenoid bed is prepared. A fresh-frozen distal tibial allograft is then fashioned, washed of marrow elements, and enhanced with platelet-rich plasma before being fixed to the glenoid with use of 2 cortical screws in a lagged fashion. The capsule and subscapularis split are then closed to complete the repair. Alternatives to revision glenoid reconstruction with distal tibial allograft include reconstruction with an iliac crest autograft, distal clavicular autograft, revision coracoid transfer, or nonoperative treatment through rehabilitation and activity modification. In cases of failed coracoid transfer for anterior shoulder instability with associated glenoid bone loss, distal tibial allograft is the superior revision treatment option for several reasons: it allows for an osteoarticular graft, offers flexibility in terms of graft size, and requires no donor-site morbidity. Distal tibial allograft allows active, high-risk patients to have restored and maintained stability with low complication and graft-resorption rates2. Glenoid reconstruction with a distal tibial allograft is associated with improved patient-reported outcomes from preoperatively, as well as recurrence rates of <10% and graft-union rates of >90%2. Initiating the procedure with an arthroscopic evaluation allows for a complete diagnostic examination, including the Hill-Sachs lesion, articular cartilage, and rotator cuff, as well as removal of any loose bodies, which are frequently present and sometimes difficult to visualize and access during the open procedure.A subscapularis split allows for maintenance of the subscapularis insertion on the lesser tuberosity as well as minimal disruption of the muscle fibers.A conjoined tendon tenotomy can provide improved access for hardware removal if the coracoid bone graft from the prior transferred coracoid is present.A 5.5-mm arthroscopic burr is utilized to decorticate the anterior aspect of the glenoid, which facilitates graft union because the burr allows built-in suction capability during constant irrigation, minimizing the possibility of heat necrosis.The distal tibial allograft is thoroughly lavaged to remove residual marrow elements prior to insertion in order to diminish potential immunogenicity.Two solid, fully threaded 3.5-mm cortical screws are placed in a lagged fashion to fix the distal tibial allograft to the glenoid.

Distal Tibial Allograft Bone Block for Posterior Shoulder Instability with Bone Loss: A Case Series

Distal Tibial Allograft Bone Block for Posterior Shoulder Instability with Bone Loss: A Case Series

Arthroscopic Anatomic Glenoid Repair Using Distal Tibial Allograft and an Inferior-to-Superior Capsular Shift

Traumatic anterior dislocation of the shoulder accounts for the vast majority of shoulder dislocations. Recurrence following initial traumatic dislocation is common, and the risk is increased by the presence of both bony and soft-tissue damage. Arthroscopic procedures have been described to address each of these etiologies individually but have not provided a technique to address bony and soft tissue pathology concurrently. This paper describes an all-arthroscopic, anatomic glenoid repair using distal tibial allograft with an inferior-to-superior capsular shift, addressing significant glenoid bone loss and capsular laxity with a single operation.

Arthroscopic Treatment for Shoulder Instability with Posterior Glenoid Bone Loss Using Allograft

Several anatomical features contribute to posterior shoulder instability. Isolated soft tissue procedures in the presence of a significant glenoid bony pathology can result in high recurrence rates. The recognition of glenoid bone loss is essential for the success of the chosen treatment. The primary objective is to generate a safety profile for posterior anatomic glenoid reconstruction. The secondary objective is to evaluate the clinical trends and radiological outcomes of patients who underwent this procedure. To our knowledge, there are no clinical papers on this topic to this date. This study is a retrospective review of medical charts and diagnostic images of subjects who had posterior shoulder instability with glenoid bone loss and underwent posterior anatomic glenoid reconstruction by one surgeon (IW). Data was collected from pre and post-operative evaluations. This included an assessment by the Western Ontario Shoulder Instability (WOSI) index, as well as the pre-operative and post-operative imaging. This cohort of patients consisted of nine subjects with a mean age of 33.26 ± 9.94 years at a minimum follow-up of two years. There were no intra-operative or post-operative complications. All subjects had a stable shoulder at the latest follow-up. The overall mean pre-operative and post-operative WOSI scores (± SD) at the most recent follow-up were 72.60 ± 14.98 and 18.86 ± 16.77, respectively (p<0.05). The average AP dimension of the glenoid with graft at the most recent CT follow-up was 29.78 ± 3.49 mm. All patients demonstrated graft healing, and the grafts were shown to be placed in an excellent position. Of the nine patients, two did not demonstrate resorption, six demonstrated grade 1 resorption, and one demonstrated grade 2 resorption. The average screw alpha angle was 15.8 ± 4.6. Arthroscopic posterior shoulder stabilization with distal tibia allograft reconstruction demonstrates promising clinical, functional and radiographic results with an excellent safety profile. However, further investigations are required to obtain the longevity of the positive outcomes.

Diagnosis and Management of Traumatic Anterior Shoulder Instability.

Anterior shoulder instability is the most common form of shoulder instability and is usually because of a traumatic injury. Careful patient selection is key to a favorable outcome. Primary shoulder stabilization should be considered for patients with high risk of recurrence or for elite athletes. Soft-tissue injury to the labrum, capsule, glenohumeral ligament, and rotator cuff influence the outcome. Glenoid bone loss (GBL) and type of bone loss (on-track/off-track) are important factors when recommending treatment strategy. Identification and management of concomitant injuries are paramount. The physician should consider three-dimensional CT reconstructions and magnetic resonance arthrography when concomitant injury is suspected. Good results can be expected after Bankart repair in on-track Hill-Sachs lesions (HSLs) with GBL < 13.5%. Bankart repair without adjunct procedures is not recommended in off-track HSLs, regardless of the size of GBL. If GBL is 13.5% to 25% but on-track, adjunct procedures to Bankart repair should be considered (remplissage and inferior capsular shift). Bone block transfer is recommended when GBL > 20% to 25% or when the HSL is off-track. Fresh tibia allograft or lilac crest autograft are good treatment options after failed bone block procedure.