Journal of Shoulder and Elbow Surgery最新文献

Introduction: Shoulder arthroplasty is indicated to treat pain and dysfunction associated with advanced glenohumeral osteoarthritis (GHOA). However, the relationship between preoperative pathoanatomy and clinical presentation remains unclear. The purpose of this study was to evaluate associations between radiographic pathoanatomy, physical examination findings, patient reported outcomes (PROMs), and health-related quality of life (HRQoL) in patients with advanced GHOA who elect to undergo shoulder arthroplasty.

Methods: This retrospective study included 280 patients with primary GHOA (148 males, 52.9 percent; mean age 68.5 ± 8.6 years) who were treated with anatomic total shoulder arthroplasty (aTSA, n=147), reverse total shoulder arthroplasty (RSA, n=81), or ream and run arthroplasty (RNR, n=52). Preoperative pathoanatomy was characterized using plain radiographs and CT scans and classified according to the Samilson-Prieto (SP), Kellgren-Lawrence (KL) and Walch classifications. Additional radiographic parameters were evaluated. Associations between pathoanatomy and clinical presentation were analyzed using multivariable regression. The minimal clinically important difference (MCID) was used to evaluate the clinical significance of associations.

Results: Greater humeral head flattening was associated with significantly and clinically relevant less active forward elevation (AFE) (B=-0.56, p=.048), active external rotation (AER) (B=-0.38, p=.048), and internal rotation (IR) (B=-0.06, p=.027). Larger humeral neck spur size was associated with significant and clinically relevant less AER (B=-0.40, p=.01). There were no clinically significant associations between SP grade, KL grade, Walch classification, critical shoulder angle, humeral medialization, glenoid version, or glenoid inclination and ROM or PROMs. There were no significant associations between pathoanatomy and HRQoL.

Discussion: There were limited associations between the severity of pathoanatomy in advanced GHOA and clinical presentations. The only significant associations between pathoanatomy and the clinical presentation related to the humerus, correlating with reduced ROM, but not with PROMs or HRQoL. These findings suggest that existing classification systems for GHOA may not fully capture the variability in clinical symptoms. Further research with larger cohorts, including patients with earlier stage GHOA, is needed to clarify the relationship between pathoanatomy and clinical manifestations of GHOA.

Background: Reconstruction after proximal humerus tumor resection poses challenges in restoring stability and function due to loss of rotator cuff attachments and soft-tissue integrity. Hemiarthroplasty (HA) with synthetic mesh augmentation has traditionally been used, whereas reverse total shoulder arthroplasty (rTSA) has emerged as an alternative. Comparative data between these techniques in oncologic settings remain limited. This study compared functional outcomes and complication profiles between HA with aortograft mesh (HA-aortograft) and rTSA endoprosthetic reconstructions following proximal humeral oncologic resection.

Methods: A single-center retrospective cohort study was performed on 68 patients who underwent oncologic proximal humerus resection and reconstruction with HA-aortograft (n = 58) or rTSA (n = 10) from 2000 - 2025. Functional outcomes, including forward elevation (FE), external rotation (ER) lag, and internal rotation (IR) to the hip or less, were assessed preoperatively, 6 and 12 months postoperatively, and at final follow-up. Complication, recurrence, and revision rates were recorded. Between-group comparisons used t-tests or Fisher's exact tests; within-group changes used paired tests.

Results: rTSA had shorter mean final follow-up (21.9 vs 43.5 months, P = .001) and shorter resection lengths (7 vs 12.7 cm, P < .001). rTSA demonstrated superior FE at 6 months (76° vs 34°, P = .004) and final follow-up (87° vs 41°, P = .018); this superiority persisted when restricting analysis to those with preserved deltoid insertions. Longitudinally, HA-aortograft lost significant FE function from baseline at 6 months (-36°, P = .003) and 12 months (-25°, P = .042). In contrast, rTSA achieved significant gains at 6 months (+50°, P = .015) and final follow-up (+60°, P = .023). A greater proportion of rTSA patients achieved the minimal clinically important difference for FE (≥ 12°) at 6 months (80% vs 20.6%, P = .001) and final follow-up (77.8% vs 26.5%, P = .008). Rotational outcomes were largely comparable cross-sectionally, though rTSA showed a trend toward greater improvement in ER lag and IR limitation. Rates of implant-related complication (rTSA 10% vs HA-aortograft 12.1%) and revision (rTSA 10% vs HA-aortograft 5.2%) were similar between groups.

Conclusion: rTSA endoprosthetic reconstruction provided superior restoration of FE and overall functional recovery compared with HA-aortograft following proximal humeral oncologic resection, without increased complication or revision rates.

Background: Scapular dyskinesis is frequently observed with various types of shoulder instability, but whether scapular dyskinesis could contribute to shoulder instability is still unclear. The purpose of this study was to determine the effects of scapular orientation on anterior and posterior glenohumeral translation using a cadaveric model of anterior and posterior labral tears.

Methods: Twenty fresh-frozen cadaveric shoulders were divided into two groups: the anterior lesion (n=10) and posterior lesion (n=10) groups. The humeral head was translated anteriorly or posteriorly with a constant 30 N force in the anterior or posterior tear groups, respectively. Humeral head displacement was measured at neutral scapula orientation for the intact labrum and following anterior or posterior labral tears. Following a labral tear, humeral head displacement was also measured at six additional scapular orientations (±10° increments from neutral), including downward rotation, upward rotation, posterior tilt, anterior tilt, internal rotation, and external rotation. The humerus was held at 0° of horizontal abduction and 40° of horizontal abduction (the apprehension test position) or 40° of horizontal adduction (the jerk test position) in the anterior lesion or posterior lesion groups, respectively.

Results: The presence of isolated labral tears generally increased anterior and posterior translations on the order of 1-2 mm in the neutral scapular orientation (P≤0.021). Anterior humeral head translation in 0° humeral abduction further increased by approximately 1 mm in the mean upward scapular rotation orientation (P≤0.021). In the apprehension test, anterior translation increased from posterior to anterior scapular tilt (1.3 mm, P=0.017), and from internal to external scapular rotation (1.8 mm, P≤0.006). Posterior humeral translation in 0° humeral abduction showed trends increasing from downward to upward scapular rotation (1.2 mm, P≤0.027) and posterior to anterior scapular tilt (2.8 mm, P≤0.007), while slightly decreasing from internal to external scapular rotation (0.6 mm, P=0.014). Posterior translation in the jerk test increased from downward to upward scapular rotation (0.8 mm, P≤0.012) and posterior to anterior scapular tilt (0.9 mm, P≤0.043), but slightly decreased from internal to external scapular rotation (0.6 mm, P=0.001).

Conclusion: Increased scapular upward rotation, anterior tilt, and external rotation were associated with increased anterior translation of the humeral head in shoulders with anterior labral lesions. In shoulders with posterior labral lesions, increased scapular upward rotation, anterior tilt, and internal rotation were associated with increased posterior translation of the humeral head. These findings suggest that scapular dyskinesis could contribute to instability recurrence.

Background: Frailty is a well-established predictor of poor outcomes after orthopaedic surgery. The 6-item Modified Frailty Index (mFI-6), which includes hypoalbuminemia, may provide enhanced risk stratification compared to the widely used 5-item Modified Frailty Index (mFI-5). The predictive value of the mFI-6 versus the mFI-5 for short-term complications after surgical management of proximal humerus fractures (PHFs) remains unclear.

Methods: A retrospective analysis of the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database was conducted to identify patients who underwent open reduction and internal fixation, hemiarthroplasty, or total shoulder arthroplasty for PHFs from 2011 to 2023. Patients were stratified by mFI-6 score (< 3 vs. ≥ 3). Thirty-day outcomes, including readmission, mortality, complications, hospital length of stay, and discharge disposition, were measured. Receiver operating characteristic (ROC) analysis compared the predictive performance of the mFI-6 and mFI-5 for these outcomes.

Results: A total of 30,070 patients met inclusion criteria. 5.4% were classified as highly frail (mFI-6 ≥ 3). Patients with high mFI-6 scores had significantly increased rates of readmission (9.9% vs. 2.9%), mortality (1.6% vs. 0.2%), overall complications (15.2% vs. 4.7%), non-home discharge (29.1% vs 8.6%), and longer hospital stays (4 ± 5 days vs. 2 ± 4 days) (all P-values < 0.001). After multivariate regression, these outcomes remained independently associated with high mFI-6 scores. The area under the ROC curve for the mFI-6 was highest for mortality (AUC 0.751), showing consistently superior performance compared to the mFI-5 for readmission, mortality, complications, and non-home discharge. After stratifying by procedure, such differences remained across most outcomes.

Discussion: In patients undergoing operative management of PHFs, higher mFI-6 scores are strongly associated with adverse 30-day outcomes. The mFI-6 demonstrates improved predictive ability over the mFI-5, supporting its adoption for preoperative risk stratification in patients undergoing surgery for PHFs.

Background: Lesser tuberosity osteotomy (LTO) repair in total stemless shoulder arthroplasty has a high nonunion rate and thus presents a challenge to shoulder surgeons. Improved repair techniques may mitigate nonunion from excessive fragment motion or inadequate compression. The purpose of this study was to evaluate the biomechanical properties of three LTO repair techniques in the setting of stemless shoulder arthroplasty. Tensionable cortical button (Button) and suture anchor (Anchor) constructs were compared to a reference suture with a lateral plate construct (Suture).

Methods: Forty human cadaveric shoulders from twenty matched pairs were dissected and the lesser tuberosity osteotomized. In each pair, the LTO was repaired with a Suture and lateral plate construct on one side and on the other side, either a tensionable cortical Button or suture Anchor construct was used. Sutures were passed through the humeral components of a stemless arthroplasty system during the procedures. All specimens were cycled 1000 times from 10-100 N at 1 Hz using a custom subscapularis cryoclamp. Cyclic construct gapping was recorded at regular intervals with a digital video system. All specimens were then loaded to failure, and failure load, displacement, mode, and construct stiffness were recorded. Statistical analyses compared the Suture constructs to their paired Button or Anchor constructs.

Results: Compared to their Suture pairs, the Button group displayed no differences in construct gapping (p≥0.138), but the Anchor group displayed up to 50% increased gapping from cycles 1-400 (p≤0.049). The Suture construct supported approximately 25% higher loads prior to failure when compared to their paired Button and Anchor group (p≤0.014). There were no differences in failure stiffness between the Sutures and their paired Buttons or Anchors.

Conclusion: In this controlled laboratory study, the decreased rate of initial construct gap formation and greater failure load of the suture construct suggests an environment for superior in vivo healing of the LTO as a result of decreased micromotion, with clinical implications still to be determined. Furthermore, the greater failure load in the suture construct could prevent catastrophic failure of the LTO in the delicate post-operative period. In the setting of total shoulder arthroplasty, an LTO subscapularis repair utilizing a suture with a lateral plate construct provides a biomechanically superior repair to either a tensionable cortical button or suture anchor repair.

Background: The advent of modern, precontoured locking plates has improved treatment of distal humerus fractures (DHFs) by providing an anatomic fit and a reliable locking mechanism with interdigitating screws. However, severe articular comminution may predispose surgical failure despite anatomic reduction and a biomechanically strong construct.

Methods: A retrospective review was performed to identify patients who underwent distal humerus open reduction internal fixation (ORIF) between 2015 and 2020. Fractures were classified using the AO/OTA classification and further categorized by anatomic location and number of fragments on preoperative imaging. Articular comminution was defined as the number of articular fracture fragments ≥1.5cm and stratified as high (>= 5 fragments) and low (<5 fragments) comminution. Outcomes included elbow range of motion, quick Disabilities of the Arm, Shoulder, and Hand (qDASH), and Mayo Elbow Performance Score (MEPS). Complications were classified as major or minor based on the need for reconstructive reoperation. Outcomes and complications between high and low comminution DHFs were compared using Student's t-test and Fisher's exact test.

Results: The study cohort consisted of 51 patients, 38 female (75%) and 13 male (25%), with an average age of 63.3 years. Fracture types included 9 AO/OTA type A, 7 type B, and 35 type C. At a mean follow-up of 47 months, the mean arc of motion in the high comminution group was 104° versus 109° in the low comminution group (p=0.595). The mean MEPS was 79 versus 88 (p=0.376) and mean qDASH score was 29 versus 19 (p=0.219) in the high comminution and low comminution groups respectively. Among the intra-articular fractures, patients with high comminution fractures experienced significantly more major complications (87.5% vs. 16.3%, p<0.001) and overall complications (87.5% versus 30.2%, p=0.001) compared with those in the low comminution group. Major complications in the high comminution group included bone resorption with conversion to arthroplasty and radical contracture releases with heterotopic ossification excision. Major complications in the low comminution group included nonunion, elbow contractures, deep infection, and bone resorption with implant failure. All highly comminuted fractures achieved satisfactory reduction with parallel plate fixation. Final qDASH and MEPS scores were not affected by comminution severity, although a significantly higher proportion of patients required revision surgery in the high comminution group.

Conclusion: Precontoured locking plates provide reliable fixation for intra-articular DHFs. However, severe articular comminution is associated with complications resulting in major reconstructive reoperations, even with satisfactory fixation. Despite this, conversion to total elbow arthroplasty remains low.

Background: Fatty infiltration (FI) and muscle atrophy following rotator cuff (RC) tears are largely irreversible and are major determinants of poor surgical outcomes, increased re-tear risk, and long-term functional disability. No pharmacologic therapies have been validated to prevent or reverse these degenerative changes. Glucagon-like peptide-1 receptor agonists (GLP-1RAs), including liraglutide, have demonstrated anti-adipogenic and tissue-preserving effects in other organ systems, suggesting potential application in RC-related muscle degeneration.

Purpose: To evaluate the effects of systemic liraglutide administration on FI, muscle morphology, and functional outcomes in a rat model of chronic RC tear without tendon repair.

Study design: Controlled laboratory study.

Methods: Adult male Sprague-Dawley rats underwent unilateral supraspinatus tendon transection with interposition of a silicone tube to prevent tendon-to-bone healing. Animals were randomly assigned to receive subcutaneous liraglutide (250 ㎍/kg/day) or saline for 4 weeks, starting 2 weeks post-injury. At 6 weeks post-surgery, FI was assessed using Oil Red O staining, muscle morphology was examined via hematoxylin-eosin histology, and passive shoulder range of motion (ROM) was measured with a goniometer. Neuromuscular function was evaluated through compound muscle action potential (CMAP) recordings, and FI was quantified as the percentage of red-stained FI area using ImageJ software with a uniform color-threshold algorithm.

Results: GLP-1RA significantly reduced FI compared with controls (Oil Red O-positive area: 1.11 ± 0.75% vs 11.82 ± 3.89%, p < .001) and markedly decreased adipocyte deposition on H&E staining. Passive internal rotation was preserved (79 ± 38° vs 70 ± 2°, p < .001), as was external rotation (55 ± 2° vs 48 ± 3°, p < .001). CMAP amplitudes were significantly greater in the liraglutide group (19.43 ± 8.77 mV vs 7.61 ± 3.15 mV, p = .028).

Conclusion: Systemic liraglutide administration attenuated chronic muscle degeneration after RC tear by limiting FI, preserving muscle fiber morphology, maintaining joint mobility, and supporting neuromuscular function. These findings provide preclinical justification for therapeutic repositioning of GLP-1RAs in musculoskeletal disorders characterized by irreversible fatty degeneration.