Adipose tissue is a critical regulator of osteoarthritis.

Osteoarthritis (OA), the leading cause of pain and disability worldwide, disproportionally affects individuals with obesity. The mechanisms by which obesity leads to the onset and progression of OA are unclear due to the complex interactions among the metabolic, biomechanical, and inflammatory factors that accompany increased adiposity. We used a murine preclinical model of lipodystrophy (LD) to examine the direct contribution of adipose tissue to OA. Knee joints of LD mice were protected from spontaneous or posttraumatic OA, on either a chow or high-fat diet, despite similar body weight and the presence of systemic inflammation. These findings indicate that adipose tissue itself plays a critical role in the pathophysiology of OA. Susceptibility to posttraumatic OA was reintroduced into LD mice using implantation of a small adipose tissue depot derived from wild-type animals or mouse embryonic fibroblasts that undergo spontaneous adipogenesis, implicating paracrine signaling from fat, rather than body weight, as a mediator of joint degeneration.

Age, Tear Size, Extent of Retraction, and Fatty Infiltration Associated With a High Chance of a Similar Rotator Cuff Tear in the Contralateral Shoulder Regardless of Symptoms in Patients Undergoing Cuff Repair in the Index Shoulder.

PURPOSE: To investigate the prevalence of a contralateral rotator cuff tear (RCT) in patients with a symptomatic RCT requiring repair and to determine whether findings from magnetic resonance imaging (MRI) of the affected shoulder can predict the presence of a contralateral tear. METHODS: Patients with atraumatic RCTs who had undergone arthroscopic repair between March 2019 and February 2021 were reviewed in this study. MRI of both shoulder joints was performed to evaluate the bilaterality of RCT. Demographic factors and MRI findings of index shoulders were assessed using logistic regression analysis to reveal any correlations with the presence of RCT in the contralateral shoulder. RESULTS: A total of 428 patients were enrolled in this study. When the affected shoulders had a posterosuperior rotator cuff (PSRC) or subscapularis tear including either an isolated or combined tear, 63.6% and 67.8% had the same tears on the contralateral side, respectively. A contralateral-side tear was found in 74.6% (185/248) of symptomatic cases and 44.8% (65/145) of asymptomatic cases, which represents a significant difference (P < .001). Logistic regression analysis revealed that age ≥67.5 years, tear size ≥17 mm, Goutallier grade ≥1.5, and Patte grade ≥1.5 were found to be indicative of potential contralateral PSRC tears. By contrast, the presence of a subscapularis tear in the affected shoulder was the only significant risk factor in predicting a potential subscapularis tear in the contralateral shoulder. CONCLUSIONS: Among patients with a symptomatic RCT requiring arthroscopic repair, 63.6% with a PSRC tear and 67.8% with a subscapularis tear in the affected shoulder were found to have a similar tear in the contralateral shoulder regardless of symptoms. Age, tear size, extent of retraction, fatty infiltration of PSRC tears, and the presence of subscapularis tears were identified as factors predictive of tears on the contralateral side. LEVEL OF EVIDENCE: Level IV, case series.

Anterior rotator cable disruption does not affect outcomes in rotator cuff tear with subscapularis involvement.

PURPOSE: The purpose of this study was to compare clinical and radiological outcomes after arthroscopic repair of two different rotator cuff tear configurations: anterosuperior rotator cuff tear and rotator cuff tears with subscapularis involvement. It was hypothesized that, although both tear configurations would show significant improvement in clinical outcomes after arthroscopic repair, the rotator cuff tears with subscapularis involvement where the anterior rotator cable maintains its integrity would have better clinical outcomes and structural integrity. METHODS: This study included 226 patients who underwent arthroscopic repair of anterosuperior rotator cuff tears (n = 107, group A) and rotator cuff tears with subscapularis involvement (n = 119, group B). The visual analog scale (VAS) pain score, subjective shoulder value (SSV), American Shoulder and Elbow Surgeons (ASES) score, University of California at Los Angeles (UCLA) shoulder score, and active range of motion (ROM) were assessed. Modified belly press test was performed to assess the strength of the subscapularis muscle. Cuff integrity was evaluated using magnetic resonance arthrography or computed tomographic arthrography at 6 months after operation. RESULTS: At 3-year follow-up, the VAS score, SSVs, ASES scores, UCLA shoulder scores, active ROM, and modified belly press test showed significant improvement in both groups (p < 0.001). However, these improvements showed no statistical significance between the two groups. On follow-up radiologic evaluations, no significant difference in re-tear rates between group A (25 of 107, 23.4%) and group B (23 of 119, 19.3%) was observed. CONCLUSIONS: The presence of anterior cable involvement of the anterosuperior rotator cuff tear did not affect postoperative clinical outcomes and re-tear rate compared to rotator cuff tears with subscapularis involvement where the anterior cable integrity was maintained, although the anterosuperior rotator cuff tear was associated with more significant preoperative supraspinatus fatty infiltration. Therefore, the present study determined that it would not be necessary to differentiate treatment protocols between these patterns. LEVEL OF EVIDENCE: Level III.

Comparison of arthroscopy-assisted vs. open reduction and fixation of coronoid fractures of the ulna.

PURPOSE: The purpose of this study was to compare clinical and radiographic outcomes and complications for arthroscopy-assisted vs. open reduction and fixation of coronoid fractures in patients with complex elbow fracture-dislocations. METHODS: This retrospective study analyzed patients with complex elbow fracture-dislocations who underwent surgical fixation for coronoid fractures of the ulna from March 2009 to January 2016. Subjects included those who received either arthroscopy-assisted (group A) or open surgery (group O) for coronoid fractures and concurrent reconstruction of the lateral column (radial head and/or lateral ulnar collateral ligament) with follow-up for at least 2 years. Clinical outcomes were assessed using the visual analog scale for pain, range of motion, Mayo Elbow Performance Score, and Disabilities of the Arm, Shoulder, and Hand score at 2 years after surgery. For radiographic assessment, union of the coronoid, development of heterotopic ossification, and arthritic changes were evaluated. We also reviewed surgery-related complications. RESULTS: Twenty-five patients (mean age, 40.0 ± 12.4 years) were enrolled in this study (group A, 15 patients; group O, 10 patients), and there were no statistical differences in baseline data between the 2 groups. Clinical outcomes did not differ between the 2 groups. All fractures were united and that the prevalence of heterotopic ossification and arthritic changes were similar between the 2 groups. However, operation-related complications were more common in group O than in group A (group A, 13.3%; group O, 40.0%), including 1 patient who underwent ulnar nerve neurolysis and anterior transposition at 3 months after the initial operation. CONCLUSIONS: Eliciting fewer complications, arthroscopy-assisted reduction and fixation of coronoid fractures shows union rates and clinical results comparable to open fixation in patients with complex elbow fracture-dislocation.

Intra-articular injection of steroids in the early postoperative period does not have an adverse effect on the clinical outcomes and the re-tear rate after arthroscopic rotator cuff repair.

PURPOSE: The purpose of this study was to compare clinical outcomes and structural integrity following arthroscopic rotator cuff repair, either with intra-articular injection of corticosteroids in the early postoperative period using ultrasound guidance or without it. METHODS: This study included 318 patients who underwent arthroscopic repair for either a partial-thickness or small-to-medium-sized full-thickness rotator cuff tear from 2012 to 2015. Patients were divided into two groups based on the administration of an intra-articular corticosteroids injection at 3 months after the surgery: group A (with corticosteroid injection, n = 56) and group B (without corticosteroid injection, n = 262). Functional outcomes were evaluated using the visual analog scale (VAS) pain score, subjective shoulder value (SSV), American Shoulder and Elbow Surgeons (ASES) score, University of California Los Angeles (UCLA) shoulder score, and active range of motion (ROM). Postoperative magnetic resonance arthrography (MRA) was performed 6 months postoperatively to assess structural integrity. RESULTS: At the 2-year follow-up, both groups showed no significant differences in VAS pain score (group A/B, 1.1 ± 0.9/1.1 ± 1.1), functional scores including SSV (88.5 ± 10.8/88.3 ± 10.0), ASES (90.8 ± 6.6/90.4 ± 6.9), and UCLA scores (30.2 ± 5.6/30.7 ± 5.2), and active ROM including forward flexion (151° ± 8°/153° ± 7°), external rotation (54° ± 5°/55° ± 7°), and internal rotation (10 ± 1/10 ± 2). Follow-up MRA imaging collected 6 months after surgery showed no significant difference in the re-tear rate (n.s.) between group A and B (n = 10/56, 17.9% and 45/262, 17.2%, respectively). CONCLUSIONS: Intra-articular corticosteroids injection in the early postoperative period after arthroscopic rotator cuff repair provided satisfactory pain relief and ROM improvement without increasing the re-tear rate or deteriorating clinical outcomes at the 2-year follow-up. LEVEL OF EVIDENCE: III.

Attrition of rotator cuff without progression to tears during 2-5 years of conservative treatment for impingement syndrome.

PURPOSE: The purpose of this study was to investigate the natural history of intact rotator cuff in impingement syndrome patients with concomitant spur protruding from the undersurface of acromion. METHODS: This retrospective study included 119 patients with an intact rotator cuff who underwent conservative treatment for a spur protruding from the undersurface of the acromion. The protruded spur was defined as a trapezoid- or tetragon-shaped bony protrusion with a downward peak extending more than 3 mm in length from the baseline drawn along the acromial undersurface on the coronal view of magnetic resonance imaging (MRI) or computed tomography arthrography (CTA). Functional outcomes were evaluated by the visual analogue scale for pain, subjective shoulder value, American Shoulder and Elbow Surgeons score, University of California Los Angeles shoulder score, and active range of motion (ROM). To evaluate cuff integrity, follow-up MRI, CTA, or ultrasound were performed at least 2 years after the initial presentation. RESULTS: No new rotator cuff tears were noted in any patient during the follow-up imaging studies. However, 18 patients (15%) underwent arthroscopic acromioplasty during the study period. During the arthroscopic examinations, moderate to severe attrition of the cuff was identified, although no tears were seen. At the final follow-up, pain level and shoulder function, including ROM, showed satisfactory outcomes. CONCLUSION: Spurs protruding from the acromial undersurface did not lead to rotator cuff tears during 2-5 years of conservative treatment. However, attrition of the rotator cuff was found during arthroscopic acromioplasty, suggesting that the protruding spurs caused extrinsic impingement of the cuff. LEVEL OF EVIDENCE: Therapeutic case series Level IV.

Retrospective Comparative Outcomes Analysis of Arthroscopic Versus Open Bone Graft and Fixation for Unstable Scaphoid Nonunions.

PURPOSE: To compare union rates and clinical and radiologic outcomes after arthroscopic and open bone grafting and internal fixation for unstable scaphoid nonunions. METHODS: Between March 2009 and November 2014, patients with unstable scaphoid nonunion underwent arthroscopic (group A) or open (group O) bone grafting and internal fixation. One senior surgeon alternatively performed either arthroscopic or open osteosynthesis for the same surgical indications. Visual analog scale score, grip strength, active range of motion, Mayo wrist score (MWS), and Disabilities of Arm, Shoulder, and Hand score were assessed preoperatively and postoperatively. Union was determined by computed tomography 8 to 10 weeks postoperatively with bridging trabecula at the nonunion site. Scapholunate angle (SLA), radiolunate angle (RLA), and lateral intrascaphoid angle (LISA), plus height/length ratio (HLR) served to gauge carpal bone alignment in preoperative and postoperative radiographs. Those outcomes of patients with carpal collapse deformities, who met following conditions; (1) LISA of >45° or HLR of >0.65 on computed tomography images or (2) SLA of >60° or RLA of >10° on plain radiographs, were also compared. RESULTS: Overall, 62 patients qualified for study (group A, 28; group O, 34). Union rates did not differ by patient subset (group A, 96.4%; group O, 97.1%; P â‰’ 1); and visual analog scale score, grip strength, range of motion, Mayo Wrist Score, and Disabilities of Arm, Shoulder, and Hand scores were similar at last follow-up. In radiographic assessments, SLA, RLA, and LISA were similar, whereas scaphoid HLR excelled through open technique (group A, 0.59 ± 0.07; group O, 0.55 ± 0.05; P = .002). Subgroup analysis of patients with carpal collapse deformities (group A, 9; group O, 14) showed that all radiographic measures in group A (vs group O) reflected lesser correction (SLA, 56.7° ± 7.3° vs 49.2°±9.1° [P = .049]; RLA, 9.2° ± 2.0° vs 5.7° ± 3.0° [P = .005]; LISA, 34.8° ± 4.8° vs 25.6° ± 13.0° [P = .028]; HLR, 0.66 ± 0.04 vs 0.54 ± 0.07 [P < .001]). CONCLUSIONS: Arthroscopic and open bone grafting and internal fixation in treating unstable scaphoid nonunions, did not show any significant differences in clinical and radiologic outcomes at the minimum of 2 years after operation. In scaphoid nonunions with carpal collapse deformities, open bone grafting restored better carpal alignment than arthroscopic bone grafting, although there were no differences in clinical outcomes between the 2 techniques. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Arthroscopic Wafer Procedure Versus Ulnar Shortening Osteotomy as a Surgical Treatment for Idiopathic Ulnar Impaction Syndrome.

PURPOSE: To compare clinical and radiologic outcomes and complication rates of the arthroscopic wafer procedure (AWP) and ulnar shortening osteotomy (USO) for idiopathic ulnar impaction syndrome (UIS). METHODS: From May 2009 to June 2014, 42 patients who were aged 45 years or older with idiopathic UIS underwent either the AWP or USO under the following identical surgical indications: (1) less than 4 mm of positive ulnar variance, (2) Palmer classification 2C or 2D lesion of the triangular fibrocartilage complex, (3) stable distal radioulnar joint (DRUJ) and/or lunotriquetral joint, and (4) no evidence of osteoarthritis of the DRUJ or ulnocarpal joint. The patient assignment was not randomized. Were used a visual analog scale for ulnar wrist pain; grip strength; range of motion; the Mayo Wrist Score (MWS); and the Disabilities of the Arm, Shoulder and Hand (DASH) score at 3, 6, 12, and 24 months after surgery to compare clinical outcomes. Ulnar variance, cystic changes of the lunate and triquetrum, and DRUJ arthritis on radiographs and operation-related complications were compared. RESULTS: This study evaluated 19 patients after the AWP and 23 patients after USO. At 3 months, the AWP produced significantly better outcomes than USO regarding grip strength (79.6% ± 14.3% vs 62.7% ± 12.6%, P < .001), MWS (81.8 ± 7.9 points vs 71.3 ± 14.2 points, P = .005), and DASH score (19.4 ± 8.4 vs 31.5 ± 14.0, P = .001); clinical outcomes were similar at 6, 12, and 24 months. The complication rates were 34.8% for USO and 10.5% for the AWP; complications included DRUJ arthritis (n = 4), implant irritation (n = 6), and refracture after implant removal (n = 2) in the USO group and secondary surgery (n = 1) and tendinopathy (n = 1) in the AWP group. CONCLUSIONS: The AWP and USO for idiopathic UIS with subtle positive ulnar variance achieved similar clinical and radiologic outcomes at 2 years after surgery. However, compared with USO, the AWP showed lower complication rates and better grip strength, MWS values, and DASH scores at 3 months after surgery. LEVEL OF EVIDENCE: Level III, comparative trial.

Concomitant coracoplasty during arthroscopic subscapularis repair does not yield better clinical outcomes and structural integrity.

PURPOSE: Few studies have examined whether concomitant coracoplasty is necessary to improve clinical and radiological outcomes after arthroscopic subscapularis repair. The purpose of this study was to compare clinical outcomes and structural integrity after arthroscopic repair of isolated subscapularis full-thickness tear, either with or without concomitant coracoplasty. METHODS: This study included 62 patients who underwent arthroscopic subscapularis repair either with coracoplasty (Group A, 35 patients) or without coracoplasty (Group B, 27 patients). Preoperative and postoperative visual analog scale pain scores, subjective shoulder values, University of California at Los Angeles shoulder scores, American Shoulder and Elbow Surgeon scores, subscapularis strength, and shoulder active range of motion (ROM) were assessed. Postoperative magnetic resonance arthrography (MRA) or computed tomographic arthrography (CTA) was performed 6 months postoperatively for structural integrity assessment. RESULTS: At 2-year follow-up, all functional scores and ROM improved significantly in both groups compared with preoperative values (p < 0.001). However, none of these values differed significantly between groups. On follow-up MRA or CTA images, although postoperative coracohumeral distance was significantly greater in Group A (8.4 mm ± 2.3 mm versus 7.0 mm ± 2.0 mm) (p = 0.018), the re-tear rates were not significantly different between groups (5/35 (14%) in Group A and 4/27 (15%) in Group B). CONCLUSIONS: For isolated subscapularis full-thickness tears, concomitant coracoplasty with arthroscopic repair did not produce better clinical outcomes or structural integrity than repair without coracoplasty. This suggests that concomitant coracoplasty may not be imperative during arthroscopic repair of isolated subscapularis full-thickness tears. LEVEL OF EVIDENCE: III.

Clinical outcomes of minimally invasive open reduction and internal fixation by screw and washer for displaced greater tuberosity fracture of the humerus.

BACKGROUND: The purpose of this study was to investigate clinical and radiologic outcomes of open reduction and internal fixation with a screw and washer for a displaced greater tuberosity fracture of the proximal humerus through a small incision. METHODS: We retrospectively reviewed 29 patients who underwent open reduction and internal fixation with a screw and washer for a greater tuberosity fracture of the proximal humerus. After surgery, the patients were immobilized in a brace for 4 weeks. To determine clinical outcomes, we evaluated a visual analog scale pain score; the Subjective Shoulder Value; the University of California, Los Angeles shoulder score; the American Shoulder and Elbow Surgeons score; and active range of motion. RESULTS: All patients achieved bone union within 3 months after surgery. At the 2-year follow-up, the mean visual analog scale pain score was 1.1 ± 1.1; Subjective Shoulder Value, 93.4 ± 5.3; University of California, Los Angeles shoulder score, 31.2 ± 2.7; and American Shoulder and Elbow Surgeons score, 92.6 ± 6.7. Mean active forward flexion, external rotation, and internal rotation were 144° ± 16°, 33° ± 11°, and 13.3 ± 1.7, respectively. Postoperatively, 9 patients (31%) had stiffness and pain refractory to conservative treatment and underwent arthroscopic release. CONCLUSION: Although minimal open reduction and screw and washer fixation resulted in bone union in all cases, the incidence of postoperative stiffness was relatively high in patients with displaced greater tuberosity fractures because of prolonged immobilization after surgery.

Arthroscopic debridement for septic arthritis of the shoulder joint: post-infectious arthritis is an inevitable consequence?

PURPOSE: The purpose of this study was to compare clinical outcomes and development of post-infectious arthritis of the shoulder joint after single (Group S) or repeated (Group R) arthroscopic debridement surgeries. We hypothesized that (1) repeated surgeries might be attributable to initial subchondral involvement resulting from septic arthritis and (2) the repeated surgery group would exhibit a higher incidence of post-infectious arthritic changes and inferior clinical outcomes due to prolonged resolution of the infection. METHODS: This study included 42 patients (single surgery, n = 29; repeated surgery, n = 13) who underwent arthroscopic debridement for septic arthritis and had a minimum of 2 years of postoperative follow-up data. All patients underwent preoperative magnetic resonance imaging (MRI) with gadolinium enhancement to evaluate subchondral bone involvement suspicious for osteomyelitis secondary to septic arthritis and extension of infection around the glenohumeral joint. Functional and radiological outcomes were assessed. RESULTS: Group S experienced a shorter duration (25.4 days) of infection than Group R (39.7 days) (p = 0.002). Increased signal intensity in the subchondral bone on preoperative MRI was identified in 9 patients (31%) in Group S and 5 patients (38%) in Group R. Post-infectious arthritic changes developed in 6 (21%) and 5 (38%) in Groups S and R, respectively. However, there were no significant differences between groups. At the final follow-up, there were no significant differences in functional assessments. CONCLUSION: Despite a prolonged period of infection in the repeated surgery group, there was no significant difference in development of post-infectious arthritic changes or clinical outcomes in patients requiring single or repeated surgeries. LEVEL OF EVIDENCE: Retrospective comparative study, III.

Morphologic change of nerve and symptom relief are similar after mini-incision and endoscopic carpal tunnel release: a randomized trial.

BACKGROUND: The symptoms in carpal tunnel syndrome (CTS) can be ameliorated by open and endoscopic release of the transverse carpal ligament. It is unknown whether a mini-incision or endoscopic carpal tunnel release more effectively reverses the pathological changes that are observed in the median nerve in patients with CTS and these morphologic changes correlates with the subjective outcomes after carpal tunnel release. We hypothesized that (1) at 24 weeks after surgery, the subjective outcomes of mini-incision release and endoscopic release would not differ in patients with CTS; and (2) the ultrasonographic (US) morphology of the median nerve reverses similarly after mini-incision and endoscopic release; (3) the subjective outcomes correlates with these morphologic changes. METHODS: Between November 2011 and January 2013, 67 patients with CTS in their dominant wrist were randomized to either mini-incision (n = 32) or endoscopic (n = 35) release. Each patient was assessed by both the Boston Carpal Tunnel Questionnaire (BCTQ) and the Disabilities of the Arm, Shoulder, and Hand (DASH) pre-operatively and 24 weeks' post-operation. An US examination was conducted at both time points to measure the cross-sectional area (CSA) at the inlet, middle, and outlet (CSA-I, CSA-M and CSA-O) and the flattening ratio (FR) at the middle and outlet (FR-M and FR-O) of the median nerve. RESULTS: The post-operative mean BCTQ and DASH scores were improved significantly from the pre-operative scores in both groups (p < 0.001). The mean CSA-I decreased and CSA-M and CSA-O increased similarly in both groups (by 3.3, 3.0, and 3.8 mm2 in the mini-incision group and 2.9, 3.1. and 2.7 mm2 in the endoscopic group. The mean FR-M/FR-O decreased similarly from 3.6/4.2 to 3.2/3.0 in the mini-incision group and 3.8/4.3 to 3.2/2.9 in the endoscopic group. There were no significant differences in the subjective outcome scores or median nerve measures between the two groups. Improvement in the BCTQ-S only was significantly correlated with changes in the CSA at the inlet. CONCLUSIONS: Mini-incision and endoscopic release both similarly relieved subjective symptoms and functions along with the pathological changes in the median nerve morphology along the carpal tunnel in patients with idiopathic CTS. Symptom relief after surgical decompression seems to correlate with reduced nerve swelling at carpal inlet and reversed nerve flattening inside carpal tunnel. TRIAL REGISTRATION: This study was retrospectively registered in "ClinicalTrials.gov" at Oct 18th, 2013, and the registration number was NCT01972165 .

Outcomes of Arthroscopic Decompression of Spinoglenoid Cysts Through a Subacromial Approach.

PURPOSE: To describe a spinoglenoid cyst decompression technique through a subacromial approach and its clinical outcomes after 2 years of follow-up. METHODS: From March 2008 to October 2013, 26 patients underwent arthroscopic decompression of a spinoglenoid ganglion cyst with and/or without superior labral anterior to posterior repair, and patients who were available for minimum of 2 years of follow-up were included. For functional assessments, the visual analog scale (VAS) pain score, subjective shoulder value (SSV), University of California at Los Angeles (UCLA) shoulder score, American Shoulder and Elbow Surgeon (ASES) score, and shoulder active range of motion were used to compare preoperative and postoperative follow-up values. Follow-up magnetic resonance arthrography was taken at 6 months postoperatively to evaluate incomplete decompression or recurrence of the cyst. RESULTS: In total, 21 patients were included in this study. At the 2-year follow-up, the VAS, SSV, ASES, and UCLA shoulder scores significantly improved compared with preoperative values (P < .001): VAS improved from 3.5 to 0.7 (P < .001); SSV improved from 62.9 to 93.1 (P < .001); ASES score improved from 64.3 to 94.4 (P < .001); UCLA shoulder score improved from 21.6 to 32.9 (P < .001). Also, active forward flexion improved from 153° to 158° (P = .014), and external rotation improved from 55° to 57° (P = .042) significantly, with the exception of internal rotation. The follow-up magnetic resonance arthrography was performed in 18 patients (86%), and there was no recurrence of the spinoglenoid notch cyst. CONCLUSIONS: For spinoglenoid cyst decompression, the subacromial approach was found to be effective, yielding satisfactory clinical outcomes without recurrence. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Comparative Outcome Analysis of Arthroscopic-Assisted Versus Open Reduction and Fixation of Trans-scaphoid Perilunate Fracture Dislocations.

PURPOSE: To compare union rates and clinical and radiological outcomes of arthroscopic-assisted reduction and fixation with those of open reduction and fixation in patients with trans-scaphoid perilunate fracture dislocations. METHODS: This retrospective study included consecutive patients with trans-scaphoid PLFDs who underwent arthroscopic-assisted reduction and fixation (group A) or open reduction and fixation (group O), and who were followed up for a minimum of 2 years between May 2005 and March 2013. We excluded initially missed patients. Each different surgeon who was on call had performed each experienced operation. These clinical outcomes were assessed: range of motion, grip strength, Mayo wrist score, and Disabilities of Arm, Shoulder, and Hand (DASH) score. For radiologic outcomes, the scapholunate angle, radiolunate angle, and lunotriquetral distance were measured. RESULTS: The total number of included patient was 20 (11 in group A and 9 in group O). Scaphoid union occurred in all patients except 1 individual (11 of 11 in group A, and 8 of 9 in group O). At the last follow-up, the mean flexion-extension arc was significantly greater in group A (125.0°) than in group O (105.6°) (P = .028). The mean grip strength was 81.1% that of the contralateral side in group A and 80.9% in group O (P = .594). The mean Mayo wrist score was 85.5 in group A and 79.4 in group O (P = .026), and the mean DASH score was 10.6 in group A and 20.8 in group O (P = .001); however, only the DASH score showed a minimum clinically important difference. The mean scapholunate angle, radiolunate angle, and lunotriquetral distance were similar between the 2 groups: 47.2°, 1.7°, and 2.0 mm in group A and 48.8°, 5.6°, and 2.1 mm in group O, respectively. CONCLUSIONS: Although both arthroscopic and open techniques achieved stability of the injured wrists in patients with trans-scaphoid PLFDs, it is shown that the arthroscopic-assisted technique showed a clinically meaningful better DASH score and greater flexion-extension arc with other parameters being similar. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Clavicle hook plate fixation for distal-third clavicle fracture (Neer type II): comparison of clinical and radiologic outcomes between Neer types IIA and IIB.

BACKGROUND: The purpose of this study was to investigate clinical and radiologic outcomes of clavicle hook plate fixation for distal-third clavicle fracture (Neer type II) and to compare the clinical and radiologic outcomes and complications between Neer type IIA and type IIB. METHODS: We retrospectively reviewed 35 patients who underwent open reduction and internal fixation with AO hook locking compression plate (LCP) for distal clavicle fracture, including 13 patients with Neer type IIA and 22 patients with type IIB. Visual analog scale pain score, shoulder scores (subjective shoulder value, University of California-Los Angeles shoulder score, American Shoulder and Elbow Surgeons score), and active range of motion were evaluated to determine clinical outcome. Coracoclavicular distance was measured, and that of the injured side at last follow-up was compared with that of the uninjured side to evaluate radiologic outcomes. RESULTS: AO hook LCP fixation for distal-third clavicle fracture (Neer type II) produced satisfactory radiologic outcomes, including high union rates (100%) and coracoclavicular distance maintenance, as well as satisfactory clinical outcomes, including visual analog scale score for pain, shoulder scores (subjective shoulder value, University of California-Los Angeles shoulder score, American Shoulder and Elbow Surgeons score), and active range of motion. There were no significant differences between Neer type IIA and type IIB. With regard to complications, 22.9% of patients experienced shoulder stiffness and 17.1% had subacromial erosion; however, there were no significant differences between the 2 groups. CONCLUSION: The AO hook LCP is a suitable choice for Neer type IIA and type IIB distal-third clavicle fracture fixation.

Is Arthroscopic Bone Graft and Fixation for Scaphoid Nonunions Effective?

BACKGROUND: Arthroscopic management of scaphoid nonunions has been advanced as a less invasive technique that allows evaluation of associated intrinsic and extrinsic ligamentous injuries; however, few studies have documented the effectiveness of arthroscopic treatment of scaphoid nonunions and which intraarticular pathologies coexist with scaphoid nonunions. QUESTIONS/PURPOSES: (1) What are the outcomes of arthroscopic management of scaphoid nonunions as assessed by the proportion of patients achieving osseous union, visual analog scale (VAS) pain score, grip strength, range of motion, Mayo Wrist Score (MWS), and Disabilities of the Arm, Shoulder and Hand (DASH) score? (2) What complications are associated with arthroscopic scaphoid nonunion management? (3) What forms of intraarticular pathology are associated with scaphoid nonunions? METHODS: Between 2008 and 2012, we treated 80 patients surgically for scaphoid nonunions. Of those, 45 (56%) had arthroscopic management. During that time, our general indications for using an arthroscopic approach over an open approach were symptomatic scaphoid nonunions without necrosis of the proximal fragment, severe deformities, or arthritis. Of the patients treated arthroscopically, 33 (73%) were available for followup at least 2 years later. There were five distal third, 19 middle third, and nine proximal third fractures. The mean followup was 33 months (range, 24-60 months). Union was determined by CT taken at 8 to 10 weeks after operation with bridging trabecula at nonunion site. VAS pain scores, grip strength, active flexion-extension angle, MWS, and DASH scores were obtained preoperatively and at each followup visit. The coexisting intraarticular pathologies and complications were also recorded. RESULTS: Thirty-two (97%) scaphoid nonunions healed successfully. At the last followup, the mean VAS pain score decreased (preoperative: mean 4.5 [SD 1.8], postoperative: mean 0.6 [SD 0.8], mean difference: 3.9 [95% confidence interval {CI}, 3.2-4.6], p < 0.001) and the mean active flexion-extension angle increased (preoperative: mean 100° [SD 26], postoperative: mean 109° [SD 16], mean difference: 9° [95% CI, 2-16], p = 0.017). The mean grip strength increased (preoperative: mean 35 kg of force [SD 8], postoperative: mean 50 kg of force [SD 10], mean difference: 15 kg of force [95% CI, 11-19], p < 0.001). The mean MWS increased (preoperative: mean 56 [SD 23], postoperative: mean 89 [SD 8], mean difference: 33 [95% CI, 26-41], p < 0.001) and the mean DASH score decreased (preoperative: mean 25 [SD 18], postoperative: mean 4 [SD 3], mean difference: 21 [95% CI, 15-28], p < 0.001). There were no operation-related complications and no progression of arthritis at the last followup. Seventeen patients had coexisting intraarticular pathology, including nine triangular fibrocartilage complex tears (seven traumatic and two degenerative), 17 intrinsic ligament tears (nine scapholunate interosseous ligament tears and eight lunotriquetral interosseous ligament tears), and five mild radioscaphoid degenerative changes. CONCLUSIONS: Arthroscopic management of scaphoid nonunions without severe deformities or arthritis was effective in this small series. Although intraarticular pathologies such as triangular fibrocartilage complex tears and intrinsic ligament injuries commonly coexisted with scaphoid nonunions, patients generally achieved good results. LEVEL OF EVIDENCE: Level IV, therapeutic study.

The Effect of Debridement of Coexisting Partial Ligament Injuries on Outcomes Following Arthroscopic Osteosynthesis for Minimally Displaced Scaphoid Nonunions.

PURPOSE: Partial intercarpal ligament injuries can coexist with scaphoid nonunions. However, whether these injuries should be debrided simultaneously when scaphoid nonunions are treated is unclear. The purpose of this study was to compare union rates and clinical outcomes after arthroscopic management of scaphoid nonunions, in which coexisting partial ligament injuries were, or were not, simultaneously debrided. METHODS: This retrospective study included 46 patients with scaphoid nonunions and coexisting partial intercarpal ligament injuries who underwent arthroscopy-guided bone grafting and fixation (K-wires or headless screws) between March 2008 and May 2014 with a minimum follow-up of 1 year. None of the cases had necrosis of the proximal fragment (determined by contrast-enhanced magnetic resonance imaging), severe deformities, or advanced arthritis. The partial intercarpal ligament injuries were either simultaneously debrided (25 patients; group D) or not debrided (21 patients; group ND). Visual analog scale pain scores, grip strength, flexion-extension arc of the wrist, Mayo Wrist Scores, and Disabilities of Arm, Shoulder, and Hand scores were used to compare clinical outcomes between the 2 groups. RESULTS: The nonunions united in 93% (43 of 46) of the patients. There were no differences between the 2 groups with regard to patient demographics, preoperative outcome measures, location of scaphoid nonunion, and degree of ligament injury. The overall union rate was similar between group D (92%; 23 of 25) and group ND (95%; 20 of 21). At a median follow-up of 24 months for group D and group ND, the visual analog scale pain score, grip strength, Mayo Wrist Scores, and Disabilities of the Arm, Shoulder, and Hand scores were significantly improved in both groups, compared with preoperative scores. Flexion-extension arc showed no change in both groups compared with preoperative angles. All of the follow-up measurements were similar in the 2 groups. CONCLUSIONS: In patients who underwent arthroscopic bone grafting and fixation of scaphoid nonunions, simultaneous debridement of incidentally found partial intercarpal ligament injuries did not result in a better union rate or clinical outcomes than not debriding the partial ligament injuries. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic III.

Optimal immobilization position for conservative treatment of proximal humerus fractures by fracture type: a biomechanical cadaveric study.

In conservative treatment for proximal humerus fractures (PHFs), the immobilization position of the affected arm should not be determined uniformly. The aim of this study is to investigate the optimal immobilization position for conservative treatment of different types of PHFs. We hypothesized that the optimal position minimizing the deforming force in PHFs depends on the fracture components involved. PHF models involving either the surgical neck (SN) or greater tuberosity (GT) were created using 12 fresh-frozen cadaveric shoulders. In the SN model, the deforming forces on the pectoralis major muscle were measured in full adduction by increasing external rotation. In the GT model, the deforming force of the supraspinatus muscle was measured in neutral rotation by decreasing abduction, and the deforming force of the infraspinatus muscle was measured in full adduction by increasing internal rotation, respectively. In the SN model, the deforming force of the pectoralis major muscle increased significantly with external rotation from full internal rotation to neutral rotation (P = 0.006), indicating that the arm should be placed in full internal rotation. In the GT model, the deforming force of the supraspinatus muscle increased significantly with adduction from 45° of abduction to full adduction (P = 0.006); the deforming force of the infraspinatus muscle increased significantly with internal rotation from neutral rotation to full internal rotation (P = 0.006). These findings should be considered when placing the arm in abduction and neutral rotation so as to minimize the deforming force by either the supra or infraspinatus muscle. In conservative treatment for PHFs, the affected arm should be placed in a position that minimizes the deforming force on the fracture components involved.

Examining the Efficacy of Arthroscopic Scaphocapitate Arthrodesis for Advanced Kienbock's Disease: Clinical and Radiological Outcomes.

Background: Altering wrist biomechanics, Kienbock's disease leads to progressive carpal collapse that results in early arthritis and degenerative changes. By shifting the loading axis toward the radioscaphoid joint, scaphocapitate arthrodesis (SCA) has been reported as a salvage procedure effective in treating symptomatic patients with advanced Kienbock's disease. In this study, we aimed to evaluate the clinical and radiological outcomes of arthroscopic SCA in symptomatic patients with advanced stages of Kienbock's disease. Methods: Between March 2010 and February 2021, we included 15 patients with symptomatic stage IIIA (n=2) and stage IIIB (n=13) Kienbock's disease who were followed up for a minimum of 24 months after arthroscopic SCA with or without lunate excision. The lunate was excised in 6 patients and retained in 9. Visual analog scale (VAS) pain score, grip strength, range of motion (ROM), active flexion-extension arc, and modified Mayo wrist score (MMWS) were measured preoperatively and at each follow-up examination after surgery. Operation-related complications and radiographic changes were also assessed. Results: There were 13 women and 2 men, with a mean age of 57.6 years (range, 21-74 years) at the time of undergoing arthroscopic SCA. Follow-up ranged from 24 to 116 months, with an average of 56.9 ± 32.3 months. Bony union was achieved in all patients. At preoperative examination, wrist ROM (67%) and grip strength (48%) significantly decreased, compared to the contralateral wrist. At the final follow-up, there were significant improvements in VAS, grip strength, and MMWS, whereas the active wrist ROM showed no significant change. Radioscaphoid angle recovered after surgery, while radiographic carpal collapse and ulnar translation of the carpus occurred. In subgroup analysis according to excision of the lunate, there were no significant differences in VAS, MMWS, grip strength, or total ROM. However, increased ulnar translation and decreased radial deviation were noted in the lunate excision group. Conclusions: Arthroscopic SCA achieved significant improvements in pain and wrist function in patients with advanced Kienbock's disease without any complications. Excision of the lunate when performing arthroscopic SCA seemed to induce progressive carpal ulnar translation, with no apparent clinical benefits over retaining it.

Anatomical considerations for nerve transfer in axillary nerve injury.

This study investigated the anatomical details of the axillary and radial nerves in 50 upper limbs from 29 adult formalin-embalmed cadavers, and ten fresh upper limbs. The focus was on understanding the course, division, and ramifications of these nerves to improve treatment of shoulder dysfunction caused by axillary nerve damage. The axillary nerve divided anteriorly and posteriorly before passing the quadrangular space in all specimens, with specific distances to the first ramifications. It was found that the deltoid muscle's clavicular and acromial parts were always innervated by the anterior division of the axillary nerve, whereas the spinous part was variably innervated. The longest and thickest branches of the radial nerve to the triceps muscles were identified, with no statistically significant differences in fiber numbers among triceps branches. The study concludes that nerve transfer to the anterior division of the axillary nerve can restore the deltoid muscle in about 86% of shoulders, and the teres minor muscle can be restored by nerve transfer to the posterior division. The medial head branch and long head branch of radial nerve were identified as the best donor options.