Moment arms of the coracobrachialis and short head of biceps following a Latarjet procedure: a modeling study.

BACKGROUND: The Latarjet procedure transfers the coracoid process to the anterior glenoid. This prevents recurrent anterior humeral dislocation but alters the origins of the coracobrachialis (CBR) and short head of the biceps (SHB). The impact of this alteration on the moment arms of these muscles has not been examined. METHODS: The Newcastle Shoulder Model was updated with 15 healthy cadaveric bone models to create customized shoulder models. The CBR and SHB muscles were attached to the anterior glenoid via an elliptical wrapping object. Muscle moment arms were calculated for abduction, forward flexion, scapular plane elevation, and internal rotation with 20° and 90° of abduction. Statistical comparison of moment arms between native and Latarjet shoulders was performed using spm1D. RESULTS: By transferring the origins of the CBR and SHB to the anterior glenoid, both muscles had extension moment arms during glenohumeral elevation in the coronal, sagittal, and scapular planes. Their average moment arms during abduction (-30.4 ± 3.2 mm for CBR and -29.8 ± 3.0 mm for SHB) and forward flexion (-26.0 ± 3.1 mm for CBR and -26.2 ± 3.2 mm for SHB) suggested that their role after the Latarjet procedure changed compared with their role in the native shoulder (P < .001). At higher abduction levels, both the muscles had higher internal rotation moment arms compared with the native shoulder. CONCLUSION: The Latarjet procedure affected the moment arms of the CBR and SHB. Both muscles had increased extension and internal rotation moment arms at higher degrees of elevation compared with the native shoulders. This finding suggests that these muscles act as dynamic stabilizers after the Latarjet procedure.

A narrative review of treatment strategies for major glenoid defects during primary reverse shoulder arthroplasty, with a focus on the use of structural bone graft.

Structural glenoid defects are common during primary reverse shoulder arthroplasty (RSA) and are often associated with poor outcomes. The lack of pre-operative imaging protocols for determining the depth and degree of glenoid wear hinders our ability to accurately plan and correct these defects. Although bone grafting has been reported to be effective in reducing glenoid wear during RSA, there is limited information on when to utilise it and how to prepare the graft. We conducted this review to assess the evidence for the management of glenoid defects, with an emphasis on bone grafts to treat structural glenoid bone loss in primary RSA patients.

Surgical management of distal humerus gunshot fractures: descriptive case series.

PURPOSE: The purpose of this study was to report our 5 years surgical experience and the rate of neurovascular injury following gunshot fractures of the distal humerus in a in level-1 Trauma Centre in South Africa. METHODS: A retrospective case series of 25 consecutive adult gunshot injuries to the distal humerus. Demographic and injury data were extracted from clinical case notes and electronic operative records. Imaging archives were used to classify fractures according to the AO/OTA classification. RESULTS: Twenty-five male patients, with mean age of 32-years-old, sustained gunshot injuries to the distal humerus. Eleven patients had multiple gunshots. Forty-four percent of patients underwent Computed Tomography Angiography (CTA), 20% had confirmed brachial artery injury. Limbs with vascular injury were salvaged with arterial repair and external fixation. Fractures were extra-articular in 20 cases (80%). Nineteen fractures were classified as highly comminuted. Nerve injuries occurred in 52% and were all managed expectantly. Only 32% of patients attended follow-up beyond 3 months. CONCLUSIONS: These are rare challenging injuries with high rates of neurovascular damage. This demographic of patients is poorly compliant with follow up highlighting the need for high-quality early care. Brachial artery injury should be excluded with CTA and can be managed with arterial repair and external fixation. All fractures in this series were surgically managed with conventional anatomical plate and screw fixation techniques. For nerve injury, we advocate expectant management. LEVEL OF EVIDENCE: IV.

Characterizing moment arms of the coracobrachialis and short head of biceps in native shoulders and after reverse total shoulder arthroplasty during elevation and rotation: a modeling study.

BACKGROUND: Reverse total shoulder arthroplasty (RTSA) alters the line of action of muscles around the glenohumeral joint. The effects of these changes have been well characterized for the deltoid, but there is limited information regarding the biomechanical changes to the coracobrachialis (CBR) and short head of biceps (SHB). In this biomechanical study, we investigated the changes to the moment arms of the CBR and SHB due to RTSA using a computational model of the shoulder. METHODS: The Newcastle Shoulder Model, a pre-validated upper-extremity musculoskeletal model, was used for this study. The Newcastle Shoulder Model was modified with bone geometries obtained from 3-dimensional reconstructions of 15 nondiseased shoulders, constituting the native shoulder group. The Delta XTEND prosthesis, with a glenosphere diameter of 38 mm and polyethylene thickness of 6 mm, was virtually implanted in all the models, creating the RTSA group. Moment arms were measured using the tendon excursion method, and muscle length was calculated as the distance between the muscle's origin and insertion points. These values were measured during 0°-150° of abduction, forward flexion, scapular-plane elevation, and -90° to 60° of external rotation-internal rotation with the arm at 20° and 90° of abduction. Statistical comparisons between the native and RTSA groups were analyzed using 1-dimensional statistical parametric mapping (spm1D). RESULTS: Forward flexion moment arms showed the greatest increase between the RTSA group (CBR, 25.3 ± 4.7 mm; SHB, 24.7 ± 4.5 mm) and native group (CBR, 9.6 ± 5.2 mm; SHB, 10.2 ± 5.2 mm). The CBR and SHB were longer in the RTSA group by maximum values of 15% and 7%, respectively. Both muscles had larger abduction moment arms in the RTSA group (CBR, 20.9 ± 4.3 mm; SHB, 21.9 ± 4.3 mm) compared with the native group (CBR, 19.6 ± 6.6 mm; SHB, 20.0 ± 5.7 mm). Abduction moment arms occurred at lower abduction angles in the RTSA group (CBR, 50°; SHB, 45°) than in the native group (CBR, 90°; SHB, 85°). In the RTSA group, both muscles had elevation moment arms until 25° of scapular-plane elevation motion, whereas in the native group, the muscles only had depression moment arms. Both muscles had small rotational moment arms that were significantly different between RTSA and native shoulders during different ranges of motion. CONCLUSION: Significant increases in elevation moment arms for the CBR and SHB were observed in RTSA shoulders; these increases were most pronounced during abduction and forward elevation motions. RTSA also increased the lengths of these muscles.

Assessment and management of shoulder pain at primary care level.

Most patients with shoulder pain will initially visit their community health centre, private general practitioner or family physician, with various levels of experience in the assessment and management of shoulder conditions. Shoulder conditions will range from early, simple ailments that can be treated in the primary care setting, to post-traumatic injuries and complex pathologies requiring the expertise of an orthopaedic surgeon or a fellowship-trained shoulder surgeon. Correct assessment of the patient's shoulder condition at the index consultation is a prerequisite for appropriate management. This article sets out straightforward guidelines to help general practitioners confidently identify the patient's source of shoulder pain and initiate an appropriate management plan at primary care level. Criteria for urgent and elective referral for specialist care are also outlined.

A gender-based comparison of coracoid and glenoid anatomy: CT analysis and discussion of potential impact on the Latarjet procedure.

BACKGROUND: The success of the modified Latarjet procedure depends on proper sizing of the coracoid graft. There is no information available regarding the morphometric relationship between the glenoid cavity and the coracoid process for the South African population. This study aims at measuring the relationship between the glenoid and coracoid morphometries and investigates their gender-related differences. METHODS: Glenohumeral computerized tomography scans of 100 consecutive patients were considered for this study. Morphometric measurements were performed after aligning the coracoid and glenoid in their optimum orientation. These measurements were performed by 2 independent observers. The ratio between glenoid and coracoid measurements was calculated and statistically compared using the Mann-Whitney U test. Intraclass correlation coefficients were calculated to analyze interobserver reliability. All the statistical tests were performed in SPSS v.26, and power calculations in G∗Power v.3.1. RESULTS: An average intraclass correlation coefficient value of 0.79 suggested that the interobserver reliability was good. Except for coracoid length, statistically significant (P < .05) gender differences were observed for all the other morphometries. The coracoid width (16.5 ± 1.4 mm vs. 14.7 ± 1.4 mm) and height (13.6 ± 1.6 mm vs. 10.5 ± 1.5 mm) differed between genders by 1.8 and 3.1 mm, respectively. The glenoid anteroposterior (AP) (25.3 ± 2.9 mm vs. 23.2 ± 2.4 mm) and superioinferior (36.9 ± 1.9 mm vs. 33.7 ± 2.6 mm) measurements differed by 2.1 and 3.3 mm, respectively, between the males and the females. The ratio between the AP width of the glenoid and the coracoid height was also found to be significantly different (P < .05) between the gender groups. These morphometric ratios for the coracoid width (0.66 ± 0.09 mm vs. 0.64 ± 0.08 mm) and the coracoid height (0.55 ± 0.09 mm vs. 0.46 ± 0.07 mm) differed between genders by 0.02 and 0.09, respectively. CONCLUSION: Measurements taken from computerized tomography scans showed significant differences between genders in absolute measurements and in the ratio of the coracoid height to the glenoid AP distance. This could have implications on the ability of the Latarjet procedure to compensate for bone loss in female patients.

The modified Latarjet procedure in female patients: clinical outcomes and complications.

BACKGROUND: The aim of this study was to assess the short- and medium-term complications and clinical outcomes of female patients after a modified Latarjet procedure. A review of the literature was also conducted for outcomes of the modified Latarjet procedure in female patients and differences reported between male and female patients. METHOD: We retrospectively reviewed the clinical notes of all female patients who had modified Latarjet procedures from 2001 with at least 1 year of follow-up. Patients were interviewed for an Oxford Shoulder Score, Western Ontario Shoulder Instability Index, Oxford Shoulder Instability Score, and subjective shoulder value. A literature review was performed of the electronic database PubMed; 343 papers were assessed for clinical outcomes based on gender. RESULTS: Twenty-nine patients were available for inclusion in the study. There were 13 complications in 11 patients (34%). The median postoperative Western Ontario Shoulder Instability Index score was 433; Oxford Shoulder Score, 42; and Oxford Shoulder Instability Score, 36. The median subjective shoulder value was 87%. Of these patients, 37.5% returned to sport. The reoperation rate was 13.8%. We found no literature reporting the outcomes of the modified Latarjet procedure in female patients. CONCLUSION: There are no published data comparing outcomes of the modified Latarjet procedure in male and female patients. Female patients had a lower postoperative return to sport and shoulder scores after the modified Latarjet procedure compared with literature reports. Whereas female gender should not be a contraindication to the Latarjet procedure, selection of patients in this group may need to be more stringent.

Outcomes After Ulnar Nerve In Situ Release During Total Elbow Arthroplasty.

PURPOSE: Ulnar nerve (UN) lesions are a significant complication after total elbow arthroplasty (TEA), with potentially debilitating consequences. Outcomes from a center, which routinely performs an in situ release of the nerve without transposition, were investigated. METHODS: Eighty-three primary TEAs were retrospectively reviewed for the intraoperative management of the UN and presence of postoperative UN symptoms. RESULTS: Three patients had documented preoperative UN symptoms. One patient had a prior UN transposition. The nerve was transposed at the time of TEA in 4 of the remaining 82 elbows (5%). The indication for transposition in all cases was abnormal tracking or increased tension on the nerve after insertion of the prosthesis. Of the 4 patients who underwent UN transposition, 2 had postoperative UN symptoms. Both were neuropraxias, which resolved in the early postoperative period. The remaining 78 TEAs received an in situ release of the nerve. The incidence of postoperative UN symptoms in the in situ release group was 5% (4 of 78). Two patients had resolution of symptoms, whereas 2 continued to experience significant UN symptoms requiring subsequent transposition. Seven patients had preoperative flexion of less than 100°. Of these, 2 had a UN transposition at the time of TEA. Of the remaining 5 elbows with preoperative flexion less than 100°, 2 had postoperative UN symptoms after in situ release, with 1 requiring subsequent UN transposition. CONCLUSIONS: A 3% incidence of significant UN complications after TEA compares favorably with systematic reviews. We do not believe that transposition, which adds to the handling of the nerve and increases surgical time, is routinely indicated and should rather be reserved for cases with marked limitation of preoperative elbow flexion or when intraoperative assessment by the surgeon deems it necessary. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Total elbow arthroplasty: outcomes after triceps-detaching and triceps-sparing approaches.

BACKGROUND: Total elbow arthroplasty (TEA) is associated with high complication rates compared with other large-joint arthroplasties. The frequency and type of complication may differ, depending on the surgical approach. A comparison of outcomes with triceps-off and triceps-on approaches was investigated. METHODS: Seventy-three patients underwent 83 primary TEAs between 2003 and 2012. Forty-six elbows had a triceps-off approach, and 37 had a triceps-on approach. Results were reviewed at a mean of 4.2 years. Cementing technique was graded according to Morrey's criteria, and clinical outcomes were assessed by means of the Mayo Elbow Performance Score. RESULTS: There was no statistically significant difference between the triceps-off and triceps-on groups with regard to the patient's age, gender, preoperative Mayo Elbow Performance Score or range of motion, or previous surgery on the affected elbow. Among patients who underwent a TEA for an inflammatory arthropathy, there was a significant difference in outcome between groups with regard to final flexion, extension, arc of motion, and pronation. Cementing technique in the triceps-off group was adequate in 70%. In the triceps-on group, cementing technique was adequate in 92%. The complication rate in the triceps-off group was 32.6% and included 7 triceps ruptures. Three patients who had attempted repairs of the triceps rupture developed deep infections requiring multiple further surgeries. The complication rate in the triceps-on group was 8.1%. CONCLUSION: A triceps-on approach in TEA results in consistently good clinical outcomes with no risk of triceps rupture, and the approach does not compromise the cement mantle. We believe that this approach will reduce complication rates in TEA.

Angular stable fixation of displaced distal-third clavicle fractures with superior precontoured locking plates.

HYPOTHESIS: We reviewed the outcome of angular stable plates in addressing displaced lateral-third clavicle fractures. We investigated union, shoulder function, request for implant removal, and return to sport. Our hypothesis was that these implants provide predictable union and return to sports without the negative consequence of leaving plates in situ, reducing the requirement for a second surgery. METHODS: We undertook a retrospective review of a consecutive series of patients who underwent this surgery between 2007 and 2010. Nineteen patients with a mean follow-up of 25 months were included. Postoperative follow-up was performed at 2 weeks and monthly thereafter until union was assessed as achieved clinically and radiographically. Two telephone interviews at a mean of 7 months and 25 months postoperatively assessed shoulder function by Oxford Shoulder Score, presence of any plate or scar discomfort, need for implant removal, and return to sport. RESULTS: Nineteen patients achieved union by 4 months (median, 12 weeks; range, 6-16 weeks). The mean Oxford Shoulder Score was 46 (range, 41-48) at a mean of 7 months (range, 3-18 months) and 47 (range, 44-48) at 25 months (range, 18-48 months). Initially, 2 patients requested implant removal; later, however, both declined surgery. No plates have been removed. Four patients complained of mild plate discomfort but did not wish removal. All patients had returned to sporting activities. CONCLUSION: Angular stable plate fixation of Neer group II, type II clavicle fractures resulted in a 100% union rate with excellent return of function with no mandatory need for removal.

Pediatric atlanto-occipital dissociation: radiographic findings and clinical outcome.

STUDY DESIGN: Retrospective diagnostic feasibility study and clinical review. OBJECTIVES: To evaluate the feasibility of making an initial atlanto-occipital dissociation (AOD) diagnosis from four radiological measurements of the craniocervical relationship on lateral cervical spine x-rays and to assess the AOD patients' clinical outcomes relative to their magnetic resonance imaging (MRI) findings. METHODS: The Powers ratio, Wackenheim line, basion-dens distance (BDD), and the C1/2:C2/3 interspinous ratio were measured in 58 pediatric controls and ten MRI-confirmed patients with AOD. The ability to identify the required anatomical landmarks and make the measurements was noted and sensitivity and specificity calculated. The correspondence between the clinical presentation and outcomes for patients with AOD and their MRI features was investigated. RESULTS: Clear landmarks for measuring interspinous ratio and Wackenheim line were confirmed by all x-rays. The BDD was measureable in 90% and the Powers ratio could be calculated in only possible in 59%. The interspinous ratio and BDD offered high sensitivities and specificity. Although the Wackenheim line was consistantly measured, it conferred a low sensitivity but reasonable specificity. The Powers ratio offered high specificity with low sensitivity. On MRI, all patients with AOD had apical ligament disruption, with a high rate of interspinous ligamentous injury (8/9); prevertebral swelling (7/9); retroclival hematoma (6/9); and tectorial membrane injury (4/9). The only MRI feature associated with poor outcome was that of altered cord signal. Both patients who died had cord signal changes on T1- and T2-weighted images. The third patient with cord signal change was limited to T2 changes with a normal T1. He had a C5-L3 sensory deficit that resolved. The degree of tectorial membrane injury did not appear to influence outcome. CONCLUSIONS: The BDD and interspinous ratio offer the best measures for initial x-ray diagnosis of AOD. This will alert the surgeon to the need for MRI. These patients often have a reduced level of consciousness, thus making clinical evaluation difficult. The MRI findings, although apparently indicative of severe abnormality, did not actually correspond to outcomes except for the presence of T1 cord signal changes that matched with severe neurological impairment and subsequent death.