The Role of the Trapezius in Stabilization of the Acromioclavicular Joint: A Biomechanical Evaluation.

Background: Acromioclavicular joint (ACJ) injuries are common, and many are adequately treated nonoperatively. Biomechanical studies have mainly focused on static ligamentous stabilizers. Few studies have quantified ACJ stabilization provided by the trapezius. Purpose/Hypothesis: To elucidate the stabilization provided by the trapezius to the ACJ during scapular internal and external rotation (protraction and retraction). It was hypothesized that sequential trapezial resection would result in increasing ACJ instability. Study Design: Controlled laboratory study. Methods: A biomechanical approach was pursued, with 10 cadaveric shoulders with the trapezius anatomically force loaded to normal. The trapezius was then serially transected over 8 trials, which alternated between clavicular defects (CD) and scapular defects (SD); each sequential defect consisted of 25% of the clavicular or scapular trapezial attachment. After each defect, specimens were tested with angle-controlled scapular internal and external rotation (12°) with rotary torque measurements to evaluate ACJ stability. Results: The mean resistance in rotary torque for 12° of scapular internal rotation (protraction) with native specimens was 7.0 ± 2.0 N·m. Overall, internal rotation demonstrated a significant decrease in ACJ stability with trapezial injury (P < .001). Eight sequential defects resulted in the following significant percentage decreases in rotary torque from native internal rotation: 1.5% (25% CD; 0% SD), 5.6% (25% CD; 25% SD), 5.1% (50% CD; 25% SD), 6.5% (50% CD; 50% SD), 3.8% (75% CD; 50% SD), 7.1% (75% CD; 75% SD), 6.7% (100% CD; 75% SD), and 12.3% (100% CD 100% SD) (P < .001). The mean resistance in rotary torque for 12° of scapular external rotation (retraction) with native specimens was 7.1 ± 1.7 N·m. External rotation did not demonstrate a significant decrease in ACJ stability with trapezial injury (P = .596). The 8 sequential defects resulted in decreases in rotary torque from native external rotation of 0%, 3.8%, 4.0%, 3.2%, 3.5%, 3.4%, 4.2%, and 0.7%. Conclusion: Trapezial injury resulted in increased instability in the setting of scapular internal rotation (protraction) of the ACJ. Clinical Relevance: These findings validate the inclusion of deltotrapezial fascial injury consideration in the modified Rockwood classification system. Repair of the trapezial insertion on the ACJ may provide improved outcomes in the setting of ACJ reconstruction.

Bone Fragment Resorption and Clinical Outcomes of Traumatic Bony Bankart Lesion Treated With Arthroscopic Repair Versus Open Latarjet.

BACKGROUND: Bony Bankart lesions can perpetuate chronic anterior glenohumeral instability. When surgical treatment is pursued, several factors need to be considered to obtain optimal outcomes. PURPOSE: To (1) quantitatively describe patterns of bone fragment resorption and associated risk factors for developing glenoid bone loss (GBL) and (2) to compare clinical and radiological results of attritional bone loss treated with either the arthroscopic Bankart or the open Latarjet procedure. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A retrospective analysis of prospectively collected data was conducted for patients who underwent arthroscopic stabilization (group A1, 10%-20% GBL; group A2, >20% GBL) or open Latarjet (group B, >10% GBL) for recurrent shoulder instability with bony Bankart lesion. Patient characteristics, number of dislocations, and Western Ontario Shoulder Instability Index (WOSI) scores were obtained. Pre- and postoperative computed tomography imaging was used to quantitatively describe patterns of bone fragment resorption. RESULTS: A total of 120 consecutive patients (group A1, 40; group A2, 23; group B, 57) were included in the study, with a mean age of 25.6 years (range, 19-35 years). The average follow-up was 5.0 years for all groups (range, 4.83-5.16 years in group A1, 4.58-5.41 years in group A2, and 4.33-5.67 years in group B). The mean times between dislocation event and surgery were 12.8 months (range, 6-32 months) and 13.6 months (range, 6-38 months) for groups A and B, respectively. Redislocation rates were 7.5% in group A1 versus 13.0% in group A2, and only occurred in patients with ≥13.5% GBL. There were no redislocations for group B (0%). Patients had better WOSI scores in group B (234.1 ± 126.9) than in group A (576.1 ± 224.6) (P < .0001). In group A, smaller preoperative bone fragment size displayed a higher percentage of resorption after surgery (r = -0.64; P < .05). CONCLUSION: A significant inverse relationship exists between preoperative bone fragment size and percentage of postoperative resorption. Patients treated with arthroscopic bony Bankart repair who had final GBL ≥13.5% had worse outcomes. When planned GBL approaches 13.5% in high-demand patients, a smaller fragment size can result in worse clinical outcomes because of resorption. In these cases, choosing the open Latarjet procedure leads to better clinical results.

Patients in Whom Arthroscopic Bankart Repair is Not Enough: Evaluation and Management of Complex Anterior Glenohumeral Instability.

Arthroscopic Bankart repair has become the most common treatment option for patients who have anterior shoulder instability. Although arthroscopic Bankart repair is generally an effective treatment method, it may be insufficient for the treatment of many patients who have anterior shoulder instability. Risk factors for failure of arthroscopic Bankart repair include younger age, level and type of sport, and shoulder specific risks, such as ligamentous laxity and the presence of bone loss. Recently, researchers have defined the limits of arthroscopic Bankart repair and more clearly defined treatment options for patients who have a high risk for failure after arthroscopic Bankart repair. Surgeons must recognize patients with anterior shoulder instability in whom a more aggressive surgical approach should be considered as well as patients who have a high risk for failure after arthroscopic Bankart repair to optimize outcomes in this patient population.

Coracoid bone graft osteolysis after Latarjet procedure: A comparison study between two screws standard technique vs mini-plate fixation.

AIMS: One of the reason for Latarjet procedure failure may be coracoid graft osteolysis. In this study, we aimed to understand if a better compression between the coracoid process and the glenoid, using a mini-plate fixation during the Latarjet procedure, could reduce the amount of coracoid graft osteolysis. MATERIALS AND METHODS: A computed tomography scan analysis of 26 prospectively followed-up patients was conducted after modified Latarjet procedure using mini-plate fixation technique to determine both the location and the amount of coracoid graft osteolysis in them. We then compared our current results with results from that of our previous study without using mini-plate fixation to determine if there is any statistical significant difference in terms of corcacoid bone graft osteolysis between the two surgical techniques. RESULTS: The most relevant osteolysis was represented by the superficial part of the proximal coracoid, whereas the deep part of the proximal coracoid graft is least involved in osteolysis and has best bone healing. The current study showed a significant difference only for the deep part of the distal coracoid with our previous study (P < 0.01). DISCUSSION: To our knowledge, there are no studies in literature that show the causes of coracoid bone graft osteolysis after Latarjet procedure. CONCLUSION: Our study suggests that there is a significant difference only for the deep part of the distal coracoid in terms of osteolysis. At clinical examination, this difference did not correspond with any clinical findings. LEVEL OF EVIDENCE: Level 4. CLINICAL RELEVANCE: Prospective case series, Treatment study.

Closed hyperthermic intraperitoneal chemotherapy with open abdomen: a novel technique to reduce exposure of the surgical team to chemotherapy drugs.

BACKGROUND: Exposure of the surgical team to toxic drugs during hyperthermic intraperitoneal chemotherapy (HIPEC) remains a matter of great concern. During closed-abdomen HIPEC, operating room staff are not exposed to drugs, but the distribution of the heated liquid within the abdomen is not optimal. With open-abdomen HIPEC, the opposite is true. Although the open-abdomen method is potentially more effective, it has not become a standard procedure because of the risk of exposure of members of the team to drugs. METHODS: We present a new technique (closed HIPEC with open abdomen) which ensures protection against potentially contaminating exposure to liquids, vapours and aerosols, and allows permanent access to the whole abdominal cavity. Its principle is to extend the abdominal surgical wound upwards with a sort of "glove-box". The cutaneous edges of the laparotomy are stapled to a latex "wall expander". The expander is draped over a special L-section metal frame placed above the abdomen. A transparent cover containing a "hand-access" port, like those used in laparoscopic surgery, is fixed inside the frame. RESULTS: In 10 patients, this device proved to be hermetic for both liquids and vapours. Intra-abdominal temperature was maintained between 42 and 43 degrees C during most of the procedure. The whole abdominal cavity was accessible to the surgeon, allowing optimal exposure of all peritoneal surfaces. CONCLUSION: This technique allows optimal HIPEC, while limiting the potential toxic effects for the surgical, medical and paramedical teams.