Ligamentous healing potential of the acromioclavicular ligament following acute anatomical reconstruction.

BACKGROUND: Horizontal instability following acute acromioclavicular joint (ACJ) reconstruction still occurs with a high prevalence. Although the human acromioclavicular ligament complex (ACLC) represents the major horizontal ACJ stabilizer, experimental studies on healing characteristics are lacking. Therefore, the purpose of this histological study was to investigate the healing potential of the ACLC following acute anatomical reconstruction METHODS: In this prospective clinical-experimental study, 28 ACLC biopsies were performed in patients with complete ACJ dislocations (Rockwood type 4 or 5) during acute hook plate stabilization (IG: implantation group; n = 14) and hook plate removal (EG: explantation group; n = 14). Histological analyses included Giemsa staining, polarized light microscopy and immunostaining against CD68, αSMA and collagen type I and type III. Histomorphological evaluation entailed cell counts, collagen expression score, ligament tissue maturity index (LTMI) and descriptive analysis of specific ligamentous structures. Statistics consisted of nonparametric Mann-Whitney U tests and a level of significance of P < .05. RESULTS: Total cell counts (cells/mm2 1491 ± 296 vs. 635 ± 430; P < 0.001) and collagen III expression (3.22 ± 0.22 vs. 1.78 ± 0.41; P < 0.001) were higher in EG compared to IG. Inversely αSMA + (11 ± 9 vs. 179 ± 186; P < 0.001) and CD68 + cell counts (56 ± 20 vs. 100 ± 57; P 0.009) were significantly lower in the EG. The EG revealed a comparable reorientation of ligamentous structures. Consistently, ACLC samples of the EG (21.6 ± 2.4) displayed a high total but differently composed LTMI score (IG: 24.5 ± 1.2; P < 0.001). CONCLUSIONS: This experimental study proved the ligamentous healing potential of the human ACLC following acute anatomical reconstruction. Histomorphologically, the ACLC reliably showed a ligamentous state of healing at a mean of about 12 weeks after surgery. However, processes of ligamentous remodeling were still evident. These experimental findings support recent clinical data showing superior horizontal ACJ stability with additional AC stabilization in the context of acute ACJ reconstruction. Though, prospective clinical and biomechanical studies are warranted to evaluate influencing factors on ACLC healing and potential impacts of acute ACLC repair on clinical outcome. STUDY TYPE: Controlled Laboratory Study.

[Influencing factors and complications in open treatment of acute anterior glenoid rim fractures]. / Einflussfaktoren und Komplikationen bei offener Versorgung akuter anteriorer Glenoidrandfrakturen.

BACKGROUND: The aim of this comparative study was to evaluate the clinical radiological outcome after open treatment of acute anterior glenoid rim fractures and to analyze the influencing factors and complications. PATIENTS AND METHODS: The study included 26 patients with an average age of 51.6 years (range 27-71 years) at surgery. The mean period of follow-up was 5.1 years (range 2.0-11.1 years). The average extent of glenoid fracture involvement was 25.5 % (range 18-35%) and three fixation techniques were applied: 1) bioresorbable pins (n = 16), 2) small fragment screws (n = 5) and 3) bioresorbable suture anchors (n = 5). RESULTS: The mean score values were 80.3 points for the absolute Constant score, 87.6 points for the normalized Constant score, 88.7 points for the Rowe score, 17.4 points for the Oxford shoulder score, 10.3 points for the simple shoulder test, 13.0 points for the shoulder pain and disability index and 81.5 % for the subjective shoulder value. The fixation technique did not show a significant influence; however, multi-fragment fractures were associated with a significantly inferior absolute (73 vs. 87 points, p = 0.022) and normalized Constant scores (81 vs. 94 points, p = 0.019). Subscapularis insufficiency with internal rotation deficit was found in 10 (39 %) patients and posttraumatic osteoarthritis occurred in 6 (23 %) patients. CONCLUSION: Open fixation yielded good or excellent shoulder function in 20 out of the 26 (77 %) patients and the clinical outcome primarily depended on the underlying type of fracture. Significantly inferior outcomes should be expected in patients with multi-fragment fractures. The main complications were subscapularis insufficiency and posttraumatic osteoarthritis.

[Open transosseous reconstruction of the rotator cuff: clinical outcome, influencing factors and complications]. / Offene transossäre Rekonstruktion der Rotatorenmanschette: Klinische Ergebnisse, Einflussfaktoren und Komplikationen.

BACKGROUND: Open transosseous rotator cuff reconstruction (RCR) still plays a prominent role in current treatment of rotator cuff tears. This study aimed to examine mid-term and long-term results of clinical outcome, determine influencing factors and analyze complications. PATIENTS: This retrospective cohort study included 104 Patients following standardized open transosseous RCR. After a mean follow-up period of 38.3 months (range 12-71 months) 88 Patients (89 shoulders) were available for examination. The mean age of Patients at surgery was 57.1 years (range 29-83 years). Standardized clinical examination included sonography and assessment of the absolute, relative and intra-individual constant scores (CS(abs), CS(rel), CS(intra)), Oxford shoulder score (OSS), American shoulder and elbow surgeons' score (ASESS) and single assessment numeric evaluation score (SANES). The level of significance for analysis of variance (ANOVA) was set at p < 0.05 (95% confidence interval). RESULTS: Mean values and standard deviations (σ) were: CS(abs) = 71 points (σ: 20.3), CS(rel) = 76 points (σ: 20.7), CS(intra) = 86 % (σ: 19.5), OSS(mod) = 77 points (σ: 20.6), ASESS = 73 points (σ: 23.3) and SANES = 72 % (σ: 22.0). Clinical results were superior when the complaints were initiated by trauma (p < 0.05). Patients with massive tears showed inferior results relative to all outcome measures (p < 0.05). Concomitant pathologies even without surgical relevance were associated with inferior outcome (p < 0.05). The factors surgeon, suture material and acromioplasty did not exert a significant influence. Revision surgery was required in 12 out of 89 (13.5 %) cases and re-ruptures occurred in 19.1%. CONCLUSIONS: Objective and subjective clinical results following open transosseous RCR were comparable to those of previously described open and arthroscopic techniques. Results were superior when the complaints were initiated by trauma. Massive tears and concomitant pathologies even without surgical relevance were associated with inferior clinical outcome. Open or arthroscopic acromioplasty did not add further benefits. A standardized operative procedure led to reproducible results irrespective of the factor surgeon.

Prognostic factors in nonoperative therapy for chronic symptomatic calcific tendinitis of the shoulder.

OBJECTIVE: To define prognostic factors in chronically symptomatic patients with calcific tendinitis of the shoulder. METHODS: We evaluated 420 patients (488 shoulders) in the context of a prospective cohort study. Epidemiologic data were assessed. The radiographic and sonographic appearance of the calcific deposits was classified. The mean period of nonoperative therapy was 4.4 years (range 0.5-13.7 years). After referral to our institution, standardized nonoperative therapy was continued for a minimum of 3 months. Failure of nonoperative therapy was defined as the persistence of symptomatic calcific tendinitis of the shoulder after a minimum of 6 months. Prognostic factors (determined at P < 0.05 by chi-square test) were analyzed by logistic regression. RESULTS: Of the 420 patients, 269 (64%) were women, 151 (36%) were men. The mean age of the patients was 51.3 years (range 28-84 years). Occurrence of calcific tendinitis of the shoulder was unilateral in 84% and bilateral in 16%. Gärtner type I calcific deposits were found in 37%, type II in 32%, and type III in 31%. Failure of nonoperative therapy was observed in 114 patients (27%). Negative prognostic factors were bilateral occurrence of calcific tendinitis of the shoulder, localization to the anterior portion of the acromion, medial (subacromial) extension, and high volume of the calcific deposit. Positive prognostic factors were a Gärtner type III deposit and a lack of sonographic sound extinction of the calcific deposit. CONCLUSION: Our findings demonstrate the existence of prognostic factors in the nonoperative treatment of chronic symptomatic calcific tendinitis of the shoulder. Guidelines for optimal treatment can be implemented according to these factors to avoid a long-term symptomatic disease course.