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.

Continuous Superior Trunk Block versus Single-Shot Superior Trunk Block with Intravenous Dexmedetomidine for Postoperative Analgesia in Arthroscopic Shoulder Surgery: A Prospective Randomized Controlled Trial.

Background/Objectives: Intravenous dexmedetomidine (DEX) can increase the analgesia duration of peripheral nerve block; however, its effect in combination with superior trunk block (STB) remains unclear. We examined whether combining single-shot STB (SSTB) with intravenous DEX would provide noninferior postoperative analgesia comparable to that provided by continuous STB (CSTB). Methods: Ninety-two patients scheduled for elective arthroscopic rotator cuff repair were enrolled in this prospective randomized trial. Patients were randomly assigned to the CSTB or SSTB + DEX group. Postoperatively, each CSTB group patient received 15 mL of 0.5% ropivacaine and a continuous 0.2% ropivacaine infusion. Each SSTB group patient received a 15 mL postoperative bolus injection of 0.5% ropivacaine. DEX was administered at 2 mcg/kg for 30 min post anesthesia, then maintained at 0.5 mcg/kg/h till surgery ended. Pain scores were investigated every 12 h for 48 h post operation, with evaluation of rebound pain incidence and opioid consumption. Results: The SSTB + DEX group had significantly higher median pain scores at 12 h post operation (resting pain, 8.0 vs. 3.0; movement pain, 8.0 vs. 5.0) and a higher incidence of rebound pain (56% vs. 20%) than the CSTB group. However, no significant between-group differences were observed in pain scores postoperatively at 24, 36, or 48 h. The CSTB group required less opioids and fewer rescue analgesics within 12-24 h post operation than the SSTB + DEX group. Conclusions: Compared with CSTB, SSTB + DEX required additional adjuvant or multimodal analgesics to reduce the risk and intensity of postoperative rebound pain in patients who underwent arthroscopic rotator cuff repair.

Heated Tobacco Products Have Detrimental Effects on Rotator Cuff Healing, Similar to Conventional Cigarettes.

BACKGROUND: Cigarette smoking impairs rotator cuff healing, but no study, to our knowledge, has focused on the association between heated tobacco products and rotator cuff tears. METHODS: This study retrospectively investigated 1,133 patients who underwent arthroscopic repair of symptomatic rotator cuff tears between March 2011 and April 2021. Patients were grouped on the basis of their smoking patterns as nonsmokers, cigarette smokers, and heated tobacco smokers. Propensity score matching was used to reduce selection bias, and 45 subjects were selected from each group via 1:1:1 matching. Functional scores and active range of motion were compared among the 3 groups preoperatively and at a 2-year follow-up. Postoperative magnetic resonance imaging was performed 6 months after the surgical procedure to assess structural integrity. RESULTS: Except for sex, similar baseline characteristics were achieved after propensity score matching. There were no differences in the clinical scores or range of motion between the matched groups either preoperatively or at the 2-year follow-up. However, the retear rate for the matched nonsmoker group was significantly lower (8.9%) than those for the matched cigarette smoker group (31.1%) and the heated tobacco smoker group (28.9%) (p = 0.022). Multivariable logistic regression analysis revealed that the retear rates were 3.403 times higher for the cigarette smoker group and 3.397 times higher for the heated tobacco smoker group than that for the nonsmoker group. CONCLUSIONS: Heated tobacco users, like conventional cigarette smokers, have worse clinical outcomes with respect to rotator cuff healing than nonsmokers. Regardless of the type of cigarette, abstinence from smoking is necessary for patients undergoing rotator cuff repair surgery. LEVEL OF EVIDENCE: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

The Treatment of Periprosthetic Fracture Revision of the Humerus with "Bamboo Support" Structural Allograft Technique-Atrophic Non-Union of a Post-Operative Periprosthetic Fracture after Reverse Total Shoulder Arthroplasty: A Case Report.

Periprosthetic fractures are a serious complication of joint replacement surgery. With the growing prevalence of reverse total shoulder arthroplasty (RTSA), the incidence of relatively uncommon periprosthetic humeral fractures has increased. Here, we present the unique case of a 74-year-old woman who developed atrophic non-union after plate osteosynthesis for a periprosthetic fracture associated with RTSA. Fixation failure was evident 3 months after the surgical intervention; the patient underwent a 3-month course of arm sling immobilization. However, bone resorption continued, and varus angulation of the fracture developed. In this case, surgical strategy involved the use of long proximal humerus internal locked system plate (DePuy Synthes, Paoli, PA, USA), augmented with autologous iliac bone graft and allogenic humerus structural bone graft with the "bamboo support technique", fixed with Cable System (DePuy Synthes, Paoli, PA, USA). No reports have addressed the management of failed periprosthetic fractures using allogeneic humeral strut bone grafts. This report aims to fill the gap by presenting a novel surgical technique for the management of periprosthetic fractures associated with RTSA in case of treatment failure.

Comparing the Biomechanical Stability of Cerclage Cable with Plate Insert Versus Locking Screw in Periprosthetic Humeral Fracture.

BACKGROUND: In the setting of periprosthetic humeral fractures, the humeral stem of the implant represents a substantial challenge to the optimal method of proximal fixation. This study aimed to compare the initial biomechanical stability provided by cerclage cables with a locking plate insert versus bicortical locking screws (i.e., the gold standard for fixation) in fresh cadaveric humeri. METHODS: After calculating the sample size, we utilized 10 sets of cadaveric specimens and created a 5-mm osteotomy gap 120 mm distal to the tip of the greater tuberosity, simulating a Wright and Cofield type-B periprosthetic humeral fracture on each specimen. Using 3 locking screws for distal fragment fixation, identical in all specimens, the specimens were assigned to Group A (3 cerclage cables with a plate insert) or Group B (3 locking bicortical screws) for proximal fragment fixation. Biomechanical tests included stiffness in varus and valgus bending, torsion, and axial compression, and a single load to failure. RESULTS: No significant differences were observed in the biomechanical metrics between the 2 groups. CONCLUSIONS: Our study revealed that fixation with use of cerclage cables with a plate insert demonstrated biomechanical stability comparable with that of bicortical locking screw fixation when addressing the proximal fragment in Wright and Cofield type-B periprosthetic humeral fractures. CLINICAL RELEVANCE: For proximal fragment fixation of periprosthetic humeral fractures, cerclage cables with a plate insert can be utilized as an effective fixation method that offers initial fixation strength that is comparable to the use of 3 locking bicortical screws.

Congruent Concavity Restoration of the Reconstructed Glenoid After the Latarjet Procedure: Compensation for the Position of the Graft.

BACKGROUND: Few clinical studies have addressed concavity restoration by natural remodeling after a Latarjet procedure. This study investigated the fibrous tissue and osseous remodeling of the reconstructed glenoid and concavity restoration after a Latarjet procedure using postoperative computed tomographic arthrography (CTA). METHODS: This retrospective study included 31 patients who underwent immediate postoperative computed tomographic (CT) scanning followed by CTA at 6 months postoperatively. We investigated whether fibrous tissue was newly created over the graft, whether the created fibrous tissue restored the congruity of the articular surface and the osseous remodeling of the graft to the glenoid level (whether the osseous portion of the graft was remodeled flush to the glenoid level) and the concavity of the glenoid using the radius of a best-fit circle on the articular surface, and the relationship between the amount of created fibrous tissue and the position of the graft. RESULTS: In all patients, the fibrous tissue on the graft yielded a smooth articular surface, as revealed by the CTA. The mean radius of the entire glenoid, including the transferred graft, was significantly smaller (p = 0.010) at 33.2 ± 8.5 mm than that of the glenoid posterior to the osseous step-off at 37.6 ± 9.4 mm, which is presumed to be the glenoid before the surgical procedure. Despite the congruity of the articular surfaces due to fibrous tissue seen in the CTA, 14 (45%) of 31 patients showed a subchondral osseous step-off on either the medial side or the lateral side in the immediate postoperative CT scans. However, through osseous remodeling, 8 of the 10 grafts with a lateral step-off and 2 of the 4 grafts with a medial step-off converted to a flush position. The position of the step-off was correlated with the thickness of the fibrous tissue, with a tendency for thicker tissue in cases of a step-off on the medial side (p = 0.014). CONCLUSIONS: Fibrous tissue formation plus remodeling of the transferred graft resulted in the restoration of a congruent concavity after a Latarjet procedure by compensating for initially non-flush positioning of the graft. However, due to the small sample size in our study, clinical outcomes could not be correlated with radiographic findings, and our recommendation is to continue placing the graft as anatomically as possible. LEVEL OF EVIDENCE: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.