Limited benefits of the direct anterior approach in primary hip arthroplasty: A prospective single centre cohort study.

BACKGROUND: Since years a discussion is held on the best approach to perform total hip replacement (THR). Risk of dislocation, abductor weakness and a possible difference in rehabilitation are mentioned. We performed this study to objectify that the use of the direct anterior approach (DAA) results in a faster rehabilitation after THR compared to the non-DAA (posterolateral and anterolateral) approach. METHODS: A single centre prospective cohort study was conducted. Pre- and 16-weeks postoperative completed PROMs like the VAS, PSC, GPE and HOOS were analyzed. A leg press and power test were performed. Functional capacity was determined by the TUG and the 6MWT. RESULTS: A total of 119 patients were included for analysis: 87 in the DAA group, 32 in the non-DAA group. There were no differences in general baseline characteristics. The length of stay was significant (p = .000) shorter in the DAA group. At 16 weeks, the DAA group showed a significant greater improvement with respect to the VAS and HOOS. Also significant differences for all strength, power and functional capacity parameters between the pre- and postoperative measurements were found. A subgroup analysis at 6-weeks postoperative showed significant improvements in the TUG (p = .009) and 6MWT (p = .009) in the DAA group, but not in the non-DAA group. CONCLUSION: PROMs, strength, power and functional capacity tests show significant improvement in all approaches after THR. There seems to be a small advantage in favour of the DAA, in particular directly postoperative and the first postoperative weeks.

A biomechanical assessment of superior shoulder translation after reconstruction of anterior glenoid bone defects: The Latarjet procedure versus allograft reconstruction.

BACKGROUND: The coracoacromial ligament (CAL) is an important restraint to superior shoulder translation. The effect of CAL release on superior stability following the Latarjet is unknown; therefore, our purpose was to compare the effect of two Latarjet techniques and allograft reconstruction on superior instability. MATERIALS AND METHODS: Eight cadaveric specimens were tested on a simulator. Superior translation was monitored following an axial force in various glenohumeral rotations (neutral, internal, and external) with and without muscle loading. Three intact CAL states were tested (intact specimen, 30% glenoid bone defect, and allograft reconstruction) and two CAL deficient states (classic Latarjet (classicLAT) and congruent-arc Latarjet (congruentLAT)). RESULTS: In neutral without muscle loading, a significant increase in superior translation occurred with the classicLAT as compared to 30% defect (P = 0.046) and allograft conditions (P = 0.041). With muscle loading, the classicLAT (P = 0.005, 0.002) and the congruentLAT (P = 0.018, 0.021) had significantly greater superior translation compared to intact and allograft, respectively. In internal rotation, only loaded tests produced significant results; specifically, classicLAT increased translation compared to all intact CAL states (P < 0.05). In external rotation, only unloaded tests produced significant results with classicLAT and congruentLAT allowing greater translations than intact (P ≤ 0.028). For all simulations, the allograft was not significantly different than intact (P > 0.05) and no differences (P = 1.0) were found between classicLAT and congruentLAT. DISCUSSION: In most simulations, CAL release with the Latarjet lead to increased superior humeral translation. CONCLUSION: The choice of technique for glenoid bone loss reconstruction has implications on the magnitude of superior humeral translation. This previously unknown effect requires further study to determine its clinical and kinematic outcomes.

Classic versus congruent coracoid positioning during the Latarjet procedure: an in vitro biomechanical comparison.

PURPOSE: The purpose of this biomechanical study was to compare the classic Latarjet technique and congruent-arc modification with respect to glenohumeral stability, joint stiffness, translation, and range of motion. METHODS: Eight cadaveric forequarters were tested on a shoulder simulator that applied loads independently to the conjoint tendon, long head of biceps, rotator cuff, and deltoid. The test conditions included: intact, 30% glenoid defect, and reconstruction of the defect with the classic and congruent Latarjets. The Latarjet techniques were randomly ordered, with the outcome variables being anterior dislocation, glenohumeral translation, rotational range of motion, and joint stiffness. RESULTS: All 8 specimens dislocated after creation of a 30% glenoid defect. The classic Latarjet stabilized 7 of 8 specimens, whereas the congruent-arc modification stabilized all specimens (8/8). In abduction neutral rotation, there was no difference in joint translation between techniques (P = .613). In abduction external rotation, there was significantly greater anterior humeral head translation after the congruent technique than after the classic (9.9 and 6.5 mm, respectively, P = .013). Rotational range of motion was significantly reduced after classic (-25.8°) and congruent (-22.2°) transfers as compared with the 30% defect (P ≤ .041). Joint stiffness in the abducted, externally rotated position was significantly reduced in the 30% defect as compared with intact (P = .012), congruent (P = .015), and classic (P < .001) conditions. In all abduction positions, the intact was not significantly different from the Latarjet techniques, and the techniques did not significantly differ from each other (P ≥ .102). CONCLUSIONS: The classic and congruent-arc Latarjet techniques restore shoulder stability and motion in cases of considerable bone loss. The techniques do not substantially differ in rotational range of motion or joint stiffness. The congruent-arc technique, however, does result in significantly greater anterior humeral head translation, as compared with the classic technique, before reaching a stable non-dislocated endpoint. CLINICAL RELEVANCE: On the basis of this biomechanical model, both the classic and congruent-arc Latarjet techniques can be used to stabilize a shoulder with substantial glenoid bone loss. Further clinical and biomechanical studies are required to determine if particular clinical circumstances exist where 1 technique has an advantage over the other.

Does the dynamic sling effect of the Latarjet procedure improve shoulder stability? A biomechanical evaluation.

INTRODUCTION: Glenohumeral instability with glenoid bone loss is commonly treated with the Latarjet procedure. The procedure involves transfer of the coracoid and conjoint tendon, which is thought to provide a stabilizing sling effect; however, its significance is unknown. This study evaluated the effects of the Latarjet procedure, with and without conjoint tendon loading, on shoulder stability and range of motion (ROM). MATERIALS AND METHODS: A custom simulator was used to evaluate anterior shoulder stability and ROM in 8 cadaveric shoulders. Testing conditions included intact, 30% glenoid defect, and Latarjet with and without conjoint loading. Unloaded and 10-N loaded states were tested in adduction and 90° abduction. Outcome variables included dislocation, stiffness (neutral and 60° external rotation), and internal-external rotational ROM. RESULTS: All 30% defects dislocated in abduction external rotation. The loaded Latarjet prevented dislocation in all specimens, whereas the unloaded Latarjet stabilized 6 of 8 specimens. In abduction external rotation, there were no significant differences in stiffness between loaded and unloaded transfers (P = .176). In adduction, there were no significant differences between the intact and the loaded Latarjet (P ≥ .228); however, in neutral rotation, the unloaded Latarjet (P = .015) and the 30% defects (P = .011) were significantly less stiff. Rotational ROM in abduction was significantly reduced with the loaded Latarjet (P = .014) compared with unloaded Latarjet, and no differences were found in adduction. CONCLUSIONS: These findings indicate that glenohumeral stability is improved, but not fully restored to intact, with conjoint tendon loading. The results support the existence of the sling effect and its importance in augmenting stability provided by the transferred coracoid.

The shoulder remplissage procedure for Hill-Sachs defects: does technique matter?

BACKGROUND: This biomechanical study evaluated the effects of 3 remplissage techniques on shoulder stability and motion in a Hill-Sachs (HS) instability model. MATERIALS AND METHODS: Cadaveric forequarters were tested on an active shoulder simulator. Three remplissage techniques were performed for 15% and 30% HS defects. Testing conditions included intact and 15% and 30% HS defects, and the 3 remplissage techniques: T1, anchors in the defect valley; T2, anchors in humeral head rim; and T3, anchors in valley with medial suture placement. Outcomes included stability, internal-external rotation range of motion (IE-ROM), and joint stiffness. RESULTS: All remplissage techniques improved shoulder stability. In 15% HS defects tested in adduction, T3 significantly reduced IE-ROM (P = .037), whereas T1 and T2 did also (mean IE-ROM reductions: T1, 14°; T2, 11°; T3, 21°), but not to significance (P ≥ .088). In abduction, no significant reductions in IE-ROM occurred (P ≥ .060). In 30% HS defects tested in adduction (mean reduction IE-ROM: T1, 11°; T2, 19°; T3, 28°) and abduction (mean reduction: T1, 9°; T2, 15°; T3, 21°), all techniques significantly reduced IE-ROM (P ≤ .046). All techniques increased joint stiffness from 100% to 320% beyond the Bankart repair alone. A significant increase in joint stiffness was observed for T3 compared with the 30% HS group (P = .004), whereas T2 trended toward an increase (P = .078). There was no significant increase in joint stiffness with T1 (P = .249). CONCLUSIONS: All remplissage techniques enhanced shoulder stability, restricted ROM, and increased joint stiffness. No significant differences were found between anchors placed in the valley (T1) vs those placed in the humeral head rim (T2). Medial suture placement (T3) resulted in the greatest joint stiffness values and mean restriction in motion.

Hemiarthroplasty for humeral four-part fractures for patients 65 years and older: a randomized controlled trial.

BACKGROUND: Four-part fractures of the proximal humerus account for 3% of all humeral fractures and are regarded as the most difficult fractures to treat in the elderly. Various authors recommend nonoperative treatment or hemiarthroplasty, but the literature is unclear regarding which provides better quality of life and function. QUESTIONS/PURPOSES: We therefore performed a randomized controlled trial to compare (1) function, (2) strength, and (3) pain and disability in patients 65 years and older with four-part humeral fractures treated either nonoperatively or with hemiarthroplasty. METHODS: We randomly allocated 50 patients to one of the two approaches. There were no differences in patient demographics between the two groups. The Constant-Murley score was the primary outcome measure. Secondary outcome measures were the Simple Shoulder Test, abduction strength test as measured by a myometer, and VAS scores for pain and disability. All patients were assessed at 12 months. RESULTS: We found no between-group differences in Constant-Murley and Simple Shoulder Test scores at 3- and 12-months followup. Abduction strength was better at 3 and 12 months in the nonoperatively treated group although the nonoperatively treated patients experienced more pain at 3 months; this difference could not be detected after 12 months. CONCLUSIONS: We observed no clear benefits in treating patients 65 years or older with four-part fractures of the proximal humerus with either hemiarthroplasty or nonoperative treatment. LEVEL OF EVIDENCE: Level I, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

The effect of the remplissage procedure on shoulder stability and range of motion: an in vitro biomechanical assessment.

BACKGROUND: The remplissage procedure may be performed as an adjunct to Bankart repair to treat recurrent glenohumeral dislocation associated with an engaging Hill-Sachs humeral head defect. The purpose of this in vitro biomechanical study was to examine the effects of the remplissage procedure on glenohumeral joint motion and stability. METHODS: Cadaveric shoulders (n = 8) were mounted on a biomechanical testing apparatus that applies simulated loads to the rotator cuff and the anterior, middle, and posterior heads of the deltoid muscle. Testing was performed with the shoulder intact, after creation of the Bankart lesion, and after repair of the Bankart lesion. In addition, testing was performed after Bankart repair with and without remplissage in shoulders with 15% and 30% Hill-Sachs defects. Shoulder motion and glenohumeral translation were recorded with an optical tracking system. Outcomes measured included stability (joint stiffness and defect engagement) and internal-external glenohumeral rotational motion in adduction and in 90° of composite shoulder abduction. RESULTS: In specimens with a 15% Hill-Sachs defect, Bankart repair combined with remplissage resulted in a significant reduction in internal-external range of motion in adduction (15.1° ± 11.1°, p = 0.039), but not in abduction (7.7° ± 9.9, p = 0.38), compared with the intact condition. In specimens with a 30% Hill-Sachs defect, repair that included remplissage also significantly reduced internal-external range of motion in adduction (14.5° ± 11.3°, p = 0.049) but not in abduction (6.2° ± 9.3°, p = 0.60). In specimens with a 15% Hill-Sachs defect, addition of remplissage significantly increased joint stiffness compared with isolated Bankart repair (p = 0.038), with the stiffness trending toward surpassing the level in the intact condition (p = 0.060). In specimens with a 30% Hill-Sachs defect, addition of remplissage restored joint stiffness to approximately normal (p = 0.41 compared with the intact condition). All of the specimens with a 30% Hill-Sachs defect engaged and dislocated after Bankart repair alone. The addition of remplissage was effective in preventing engagement and dislocation in all specimens. None of the specimens with a 15% Hill-Sachs defect engaged or dislocated after Bankart repair. CONCLUSIONS: In this experimental model, addition of remplissage provided little additional benefit to a Bankart repair in specimens with a 15% Hill-Sachs defect, and it also reduced specific shoulder motions. However, Bankart repair alone was ineffective in preventing engagement and recurrent dislocation in specimens with a 30% Hill-Sachs defect. The addition of remplissage to the Bankart repair in these specimens prevented engagement and enhanced stability, although at the expense of some reduction in shoulder motion.

The effect of the conjoined tendon of the short head of the biceps and coracobrachialis on shoulder stability and kinematics during in-vitro simulation.

The kinematics and stability of the shoulder during in-vitro simulation are affected by the muscles chosen for simulation and their loads. Existing simulators have commonly actuated the rotator cuff and deltoids; however, the contribution of secondary muscles, such as those which form the conjoined tendon, are not well understood. The conjoined tendon consists of the origins of the short head of the biceps and coracobrachialis (SH&C), and is thought to produce an anterior stabilizing effect. This study investigated the effect of SH&C tension at four loading levels: 0, 5, 10, 15N. Our primary outcome variable was glenohumeral stiffness for anterior loading but internal/external rotation and extension ranges of motion were also measured. Four joint configurations were tested: adduction and 90° combined abduction, each in neutral and maximal external rotation. Increasing SH&C load resulted in a significant trend of increased glenohumeral stiffness across the average of all joint configurations (p=0.008). In abduction, neutral rotation differences were found between the stiffness at 10 and 15N compared to 0N (p=0.038 and 0.043, respectively); however, no differences were found for the three other joint configurations. There was a tendency for a decrease in the range of shoulder extension with increasing SH&C load, but this did not achieve significance (p=0.065). These findings demonstrate that the SH&C provides a stabilizing barrier effect, but only in configurations when it wraps directly anterior to the humeral head. Thus SH&C loading is likely critical to in-vitro simulation due to its effect on joint stability and kinematics.

Lengthener loosening in a reversed shoulder prosthesis: a case report.

The reverse shoulder prosthesis is designed for the treatment of glenohumeral arthritis with irreparable cuff arthropathy. Although it has given good short term results the prosthesis is not free of complications. In this case report we describe an implant-related complication.

Oncologic and functional results after treatment of giant cell tumors of bone.

Surgical treatment of giant cell tumor of bone has always been a difficult problem because of its local aggressive behavior. Oncologic results and functional outcome are reported here in a retrospective study of 36 patients, treated by various surgical procedures. The average age at the time of diagnosis was 34 years, and the median follow-up period was 7 years. Twenty-three patients were treated by intralesional excision with local adjuvant therapy, and 11 patients by extralesional excision. Two patients received radiotherapy only. Seven local tumor recurrences (30%) were encountered after intralesional procedures, while local tumor control was the rule after extralesional excision. Intralesional excision with local adjuvant therapy resulted in significantly better functional results compared with extralesional excision. Wide excision was associated with a poor functional outcome and marginal excision with a good functional outcome. For the treatment of giant cell tumor of bone, intralesional excision with local adjuvant therapy is recommended because of a good functional outcome. When applying cryosurgery as the local adjuvant, more vigorous freezing may be necessary to improve local tumor control.