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BACKGROUND: We aimed to compare tibial soft tissue and bony slopes in patients with failed and non-failed ACL reconstructions (ACLR). We hypothesized that patients with failed ACLR have increased slopes compared to non-failed ACLR, and unexplained failures have higher slopes than failures with clear technical errors and failed synthetic ligaments. METHODS: Between 2015 and 2022, 130 patients with failed ACLR were retrospectively identified; 79 knees with adequate MRI scans were analyzed. These were compared to 57 non-failed ACLRs. MRI measurements included lateral and medial tibial bony slope (LBS, MBS) and lateral and medial meniscal slope (LMS, MMS). Subgroup analysis assessed for failures with technical errors and failed synthetic ligaments. RESULTS: In all patients, the LMS and MMS reduced the bony slope towards the horizontal without reaching statistical significance. Failed ACLR had significantly higher MBS (7.1° ± 2.9 vs. 4.6° ± 2.5, p < 0.001) and MMS (5.6° ± 3.5 vs. 3.4° ± 2.8, p < 0.001). The area under the curve for MBS was 0.721 (CI: 0.628-0.813). The Youden optimal threshold value of MBS ≥ 5.1° (sensitivity 80 %, specificity 56.1 %) yielded an odd's ratio for failure of 5.1 (CI:2.3-11.6; p < 0.001). Revisions with technical errors had slopes that were not significantly different to non-failed ACLR. Revisions with synthetic grafts had MBS (7.3° ± 3.2 vs. 4.6° ± 2.5; p = 0.007) and MMS (6° ± 3.8 vs. 3.4° ± 2.8; p = 0.021) that were significantly higher to non-failed ACLR. CONCLUSION: Medial bony and meniscal slopes are higher in patients with unexplained failed ACLRs and revisions with synthetic grafts, but ACLR with technical errors failed with slopes similar to non-failed ACLRs. Increased medial slope values are a risk factor for surgical failure. LEVEL OF EVIDENCE: III.
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BACKGROUND: Subtle chronic or latent instabilities are difficult to delineate with currently available diagnostic modalities and do not allow assessment of ligamentous functionality. The noninvasive bilateral external torque computed tomography (CT) was able to reliably detect syndesmotic lesions in a cadaveric study. The aim of the study was to test the external torque device in young, healthy subjects at 3 different torque levels and to demonstrate comparability with the contralateral side. METHODS: Ten healthy subjects without history of injury or surgery to the ankle joint were enrolled in this cross-sectional study. Four CT scans were performed. During the scans, the lower legs and feet were placed in an external torque device with predefined external rotation torques of 0, 2.5, 5, and 7.5 Nm. Five different radiographic measures of syndesmotic stability were measured: anterior distance (AD), tibiofibular clear space (TCS), posterior distance (PD), external rotation (ER), and ß angle. RESULTS: With increasing external torque, slight increases in AD, ER, and ß angle were observed, whereas TCS and PD decreased slightly. Large absolute differences were found between the healthy subjects for all measured parameters, regardless of the external torque applied. Differences from the contralateral side using the same external torque were minimal for all parameters, but smallest for AD with a maximum difference of 0.5 mm. CONCLUSION: Using the healthy contralateral ankle joint is appropriate for assessing syndesmotic stability based on minimal intraindividual side differences using the external torque device. Side differences >0.5 mm in AD and >0.9 mm in PD may be considered abnormal and may indicate significant instability of the syndesmosis. However, future studies are needed to define definitive cutoff values for relevant side differences in acute and chronic syndesmotic instability to guide clinicians in their treatment decisions.
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BACKGROUND: Percutaneous pedicle screw (PPS) placement has become a pivotal technique in spinal surgery, increasing surgical efficiency and limiting the invasiveness of surgical procedures. The aim of this study was to analyze the accuracy of computer-assisted PPS placement with a standardized technique in the lateral decubitus position. METHODS: A retrospective review of prospectively collected data was performed on 44 consecutive patients treated between 2021 and 2023 with lateral decubitus single-position surgery. PPS placement was assessed by computed tomography scans, and breaches were graded based on the magnitude and direction of the breach. Facet joint violations were assessed. Variables collected included patient demographics, indication, intraoperative complications, operative time, fluoroscopy time, estimated blood loss, and length of stay. RESULTS: Forty-four patients, with 220 PPSs were identified. About 79.5% of all patients underwent anterior lumbar interbody fusion only, 13.6% underwent lateral lumbar interbody fusion only, and 6.8% received a combination of both anterior lumbar interbody fusion and lateral lumbar interbody fusion. Eleven screw breaches (5%) were identified: 10 were Grade II breaches (<2 mm), and 1 was a Grade IV breach (>4 mm). All breaches were lateral. About 63.6% involved down-side screws indicating a trend toward the laterality of breaches for down-side pedicles. When analyzing breaches by level, 1.2% of screws at L5, 13% at L4, and 11.1% at L3 demonstrated Grade II breaches. No facet joint violations were noted. CONCLUSION: PPS placement utilizing computer-assisted navigation in lateral decubitus single-position surgery is both safe and accurate. An overall breach rate of 5% was found; considering a safe zone of 2 mm, only 1 screw (0.5%) demonstrated a relevant breach. CLINICAL RELEVANCE: PPS placement is both safe and accurate. Breaches are rare, and when breaches do occur, they are lateral.
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INTRODUCTION: Distal biceps tendon repair is usually performed via a double-incision or single-incision bicortical drilling technique. However, these techniques are associated with specific complications and usually do not allow for anatomic footprint restoration. It was the aim of this study to report the clinical results of a double intracortical button anatomic footprint repair technique for distal biceps tendon tears. We hypothesized that this technique would result in supination strength comparable to the uninjured side with a low rerupture rate and minimal bony or neurologic complications. MATERIAL AND METHODS: This was a retrospective, single-surgeon cohort study of a consecutive series of 22 patients with a mean (standard deviation) age of 50.7 (9.4) years and at least 1-year follow-up after distal biceps tendon repair. At final follow-up, complications, range of motion (ROM), the Patient-rated Elbow Evaluation (PREE), Mayo Elbow Performance Score (MEPS), Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire, visual analog scale (VAS) for pain, patient satisfaction, and supination strength in neutral as well as 60° of supination were analyzed. Radiographic evaluation was performed on a computed tomography scan. RESULTS: One patient (4.5%) experienced slight paresthesia in the area of the lateral antebrachial cutaneous nerve. Heterotopic ossification was seen in 1 patient (4.5%). All patients recovered full ROM except for 1 who had 10° of loss of flexion and extension. Median PREE score was 4.6 (0-39.6), median MEP was 100 (70-100), and median DASH score was 1.4 (0-16.7). All but 1 patient were very satisfied with the outcome. The affected arm had a mean of 98% (±13%) of neutral supination strength (P = .633) and 94% (±12%) of supination strength in 60° (P = .054) compared with the contralateral, unaffected side. There were 4 cases (18.2%) of cortical thinning due to at least 1 button and 1 case of button pullout (4.5%). CONCLUSIONS: The double intracortical button anatomic footprint repair technique seems to provide reliable restoration of supination strength and excellent patient satisfaction while minimizing complications, particularly nerve damage and heterotopic ossification.
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BACKGROUND CONTEXT: Academic orthopedic journals and specialty societies emphasize the importance of two-year follow-up for patient-reported outcome measures (PROMS) after spine surgery, but there are limited data evaluating the appropriate length of follow-up. PURPOSE: To determine whether PROMs, as measured by the Oswestry Disability Index (ODI), would change significantly after 2-months postoperatively after lumbar decompression surgery for disc herniation or spinal stenosis. STUDY DESIGN: Retrospective analysis of prospectively and consecutively enrolled patients undergoing lumbar decompression surgery between 2020 and 2021 from a single surgeon spine registry. PATIENT SAMPLE: One hundred sixty-nine patients. OUTCOME MEASURES: ODI, achievement of minimum clinically important difference (MCID), revisions. METHODS: Patients without a preoperative baseline score were excluded. Completion of the ODI questionnaire was assessed at the follow-up points. The median ODI was compared at time baseline, 2-month, 1-year and 2-year follow-up. Risk of reoperation was assessed with receiver operating characteristic (ROC) analysis to identify at-risk ODI thresholds of requiring reoperation. RESULTS: Median ODI significantly improved at all time points compared to baseline (median baseline ODI: 40; 2-month ODI: 16, p=.001; 1-year ODI: 11.1, p=.001; 2-year ODI: 8, p=.001). Posthoc analysis demonstrated no difference between 2-months, 1-year and 2-year postoperative ODI (p=.9, p=.468, p=.606). The MCID was met in 87.9% of patients at 2 months, 80.7% at 1 year, and 87.3% at 2 years postoperatively. Twelve patients (7.7%) underwent revision surgery between 2 months and 2 years after the index surgery (median time to revision: 5.6 months). ROC curve analysis demonstrated that an ODI score ≥24 points at 2-months yielded a sensitivity of 85.7% and a specificity of 71.8% for predicting revision after lumbar decompression (AUC=0.758; 95% CI: 0.613-0.903). The Youden optimal threshold value of ≥24 points at 2-month postop ODI yielded an odd ratio (OR) for revision of 15.3 (CI: 1.8-131.8; p=.004). The positive predictive value (PPV) and negative predictive value (NPV) were 15.4% and 98.8%, respectively. CONCLUSION: Two-year clinical follow-up may not be necessary for future peer-reviewed lumbar decompression surgery studies given that ODI plateaus at 8 weeks. Patients with a score ≥24 points at 2-months postoperatively have a higher risk of requiring a second surgery within the first 2 years and warrant continued follow-up.
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Decompression, Surgical , Lumbar Vertebrae , Spinal Stenosis , Humans , Lumbar Vertebrae/surgery , Male , Female , Middle Aged , Spinal Stenosis/surgery , Follow-Up Studies , Retrospective Studies , Aged , Reoperation/statistics & numerical data , Intervertebral Disc Displacement/surgery , Adult , Patient Reported Outcome Measures , Disability Evaluation , Treatment OutcomeABSTRACT
BACKGROUND: The severity of fatty infiltration (FI) predicts the treatment outcome of rotator cuff tears. The purpose of this investigation was to quantitatively analyze supraspinatus (SSP) muscle FI and volume at the initial presentation and after a 3-month minimum of conservative management. We hypothesized that progression of FI could be predicted with initial tear size, FI, and muscle volume. METHODS: Seventy-nine shoulders with rotator cuff tears were prospectively enrolled, and 2 magnetic resonance imaging (MRI) scans with 6-point Dixon sequences were acquired. The fat fraction within the SSP muscle was measured on 3 sagittal slices, and the arithmetic mean was calculated (FI SSP ). Advanced FI SSP was defined as ≥8%, pathological FI SSP was defined as ≥13.5%, and relevant progression was defined as a ≥4.5% increase in FI SSP . Furthermore, muscle volume, tear location, size, and Goutallier grade were evaluated. RESULTS: Fifty-seven shoulders (72.2%) had normal FI SSP , 13 (16.5%) had advanced FI SSP , and 9 (11.4%) had pathological FI SSP at the initial MRI scan. Eleven shoulders (13.9%) showed a ≥4.5% increase in FI SSP at 19.5 ± 14.7 months, and 17 shoulders (21.5%) showed a ≥5-mm 3 loss of volume at 17.8 ± 15.3 months. Five tears (7.1%) with initially normal or advanced FI SSP turned pathological. These tears, compared with tears that were not pathological, had significantly higher initial mediolateral tear size (24.8 compared with 14.3 mm; p = 0.05), less volume (23.5 compared with 34.2 mm 3 ; p = 0.024), more FI SSP (9.6% compared with 5.6%; p = 0.026), and increased progression of FI SSP (8.6% compared with 0.5%; p < 0.001). An initial mediolateral tear size of ≥20 mm yielded a relevant FI SSP progression rate of 81.8% (odds ratio [OR], 19.0; p < 0.001). Progression rates of 72.7% were found for both initial FI SSP of ≥9.9% (OR, 17.5; p < 0.001) and an initial anteroposterior tear size of ≥17 mm (OR, 8.0; p = 0.003). Combining these parameters in a logistic regression analysis led to an area under the receiver operating characteristic curve (AUC) of 0.913. The correlation between FI SSP progression and the time between MRI scans was weak positive (ρ = 0.31). CONCLUSIONS: Three risk factors for relevant FI progression, quantifiable on the initial MRI, were identified: ≥20-mm mediolateral tear size, ≥9.9% FI SSP , and ≥17-mm anteroposterior tear size. These thresholds were associated with a higher risk of tear progression: 19 times higher for ≥20-mm mediolateral tear size, 17.5 times higher for ≥9.9% FI SSP , and 8 times higher for ≥17-mm anteroposterior tear size. The presence of all 3 yielded a 91% chance of ≥4.5% progression of FI SSP within a mean of 19.5 months. LEVEL OF EVIDENCE: Diagnostic Level II . See Instructions for Authors for a complete description of levels of evidence.
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Rotator Cuff Injuries , Humans , Rotator Cuff Injuries/diagnostic imaging , Rotator Cuff Injuries/therapy , Rotator Cuff Injuries/pathology , Prospective Studies , Rotator Cuff/pathology , Rupture , Magnetic Resonance Imaging/methodsABSTRACT
Paediatric and adolescent shoulder instability is caused by a unique combination of traumatic factors, ligamentous laxity, and pattern of muscle contractility. The multifactorial nature of its aetiology makes interpretation of the literature difficult as nomenclature is also highly variable. The purpose of this review is to summarize the existing literature and shed light on the nuances of paediatric and adolescent shoulder instability. The epidemiology, clinical features, imaging, and management of all forms of paediatric shoulder instability are presented. The main findings of this review are that structural abnormalities following a dislocation are uncommon in pre-pubertal paediatric patients. Young post-pubertal adolescents are at the highest risk of failure of non-operative management in the setting of traumatic instability with structural abnormality, and early stabilisation should be considered for these patients. Remplissage and the Latarjet procedure are safe treatment options for adolescents at high risk of recurrence, but the side-effect profile should be carefully considered. Patients who suffer from instability due to generalized ligamentous laxity benefit from a structured, long-term physiotherapy regimen, with surgery in the form of arthroscopic plication as a viable last resort. Those who suffer from a predominantly muscle patterning pathology do not benefit from surgery and require focus on regaining neuromuscular control.
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BACKGROUND: If tibiofibular syndesmotic injury is undetected, chronic instability may lead to persistent pain and osteoarthritis. So far, no reliable diagnostic method has been available. The primary objectives of this study were to determine whether defined lesions of the syndesmosis can be correlated with specific tibiofibular joint displacements caused by external rotational torque and to compare the performance of bilateral external torque computed tomography (BET-CT) and arthroscopy. Secondary objectives included an evaluation of the reliability of CT measurements and the suitability of the healthy contralateral ankle as a reference. METHODS: Seven pairs of healthy, cadaveric lower legs were tested and assigned to 2 groups: (1) supination-external rotation (SER) and (2) pronation-external rotation (PER). In the intact state and after each surgical step, an ankle arthroscopy and 3 CT scans were performed. During the scans, the specimens were placed in an external torque device with 2.5, 5.0, and 7.5 Nm of torque applied. RESULTS: The arthroscopic and CT parameters showed significant correlations in all pairwise comparisons. The receiver operating characteristic (ROC) curve analyses yielded the best prediction of syndesmotic instability with the anterior tibiofibular distance on CT, with a sensitivity of 84.1% and a specificity of 95.2% (area under the curve [AUC], 94.8%; 95% confidence interval [CI], 0.916 to 0.979; p < 0.0001) and with the middle tibiofibular distance on arthroscopy, with a sensitivity of 76.2% and specificity of 92.3% (AUC, 91.2%; 95% CI, 0.837 to 0.987; p < 0.0001). Higher torque amounts increased the rate of true-positive results. CONCLUSIONS: BET-CT reliably detects experimental syndesmotic rotational instability, compared with the healthy side, with greater sensitivity and similar specificity compared with the arthroscopic lateral hook test. Translation of these experimental findings to clinical practice remains to be established. LEVEL OF EVIDENCE: Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence.
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Ankle Joint , Tomography, X-Ray Computed , Humans , Torque , Reproducibility of Results , Ankle Joint/diagnostic imaging , Tomography, X-Ray Computed/methods , CadaverABSTRACT
Background: The aim of this study was to compare the clinical and radiographic outcomes of treatment of symptomatic mal- and/or nonunion of midshaft clavicle fractures using radiographically based free-hand open reduction and internal fixation (ORIF) or computer-assisted 3D-planned, personalized corrective osteotomies performed using patient-specific instrumentation (PSI) and ORIF. The hypotheses were that (1) patients treated with computer-assisted planning and PSI would have a better clinical outcome, and (2) computer-assisted surgical planning would achieve a more accurate restoration of anatomy compared to the free-hand technique. Methods: Between 1998 and 2020, 13 patients underwent PSI, and 34 patients underwent free-hand ORIF and/or corrective osteotomy. After application of exclusion criteria, 12/13 and 11/34 patients were included in the study. The clinical examination included measurement of the active range of motion and assessment of the absolute and relative Constant-Murley Scores and the subjective shoulder value. Subjective satisfaction with the cosmetic result was assessed on a Likert scale from 0 to 100 (subjective aesthetic value). 11/13 and 6/11 patients underwent postoperative computed tomography evaluation of both clavicles. Computed tomography scans were segmented to generate 3D surface models. After projection onto the mirrored contralateral side, displacement analysis was performed. Finally, bony union was documented. The average follow-up time was 43 months in the PSI and 50 months in the free-hand cohort. Results: The clinical outcomes of both groups did not differ significantly. Median subjective shoulder value was 97.5% (70; 100) in the PSI group vs. 90% (0; 100) in the free-hand group; subjective aesthetic value was 86.4% (±10.7) vs. 75% (±18.7); aCS was 82.3 (±10.3) points vs. 74.9 (±26) points; and rCS was 86.7 (±11.3) points vs. 81.9 (±28.1) points. In the free-hand group, 2/11 patients had a postoperative neurological complication. In the PSI cohort, the 3D angle deviation was significantly smaller (PSI/planned vs. free-hand/contralateral: 10.8° (3.1; 23.8) vs. 17.4° (11.6; 42.4); P = .020)). There was also a trend toward a smaller 3D shift, which was not statistically significant (PSI/planned vs. free-hand/contralateral: 6 mm (3.4; 18.3) vs. 9.3 mm (5.1; 18.1); P = .342). There were no other significant differences. A bony union was achieved in all cases. Conclusion: Surgical treatment of nonunion and malunions of the clavicle was associated with very good clinical results and a 100% union rate. This study, albeit in a relatively small cohort with a follow-up of 4 years, could not document any clinically relevant advantage of 3D planning and personalized operative templating over conventional radiographic planning and free-hand surgical fixation performed by experienced surgeons.
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PURPOSE: Primary glenohumeral osteoarthritis is commonly associated with static posterior subluxation of the humeral head. Scapulae with static/dynamic posterior instability feature a superiorly and horizontally oriented acromion. We investigated whether the acromion acts as a restraint to posterior humeral translation. METHODS: Five three-dimensional (3D) printed scapula models were biomechanically tested. A statistical shape mean model (SSMM) of the normal scapula of 40 asymptomatic shoulders was fabricated. Next, a SSMM of scapular anatomy associated with posterior subluxation was generated using data of 20 scapulae ("B1"). This model was then used to generate three models of surgical correction: glenoid version, acromial orientation, and acromial and glenoid orientation. With the joint axially loaded (100N) and the humerus stabilized, an anterior translation force was applied to the scapula in 35°, 60° and 75° of glenohumeral flexion. Translation (mm) was measured. RESULTS: In the normal scapula, the humerus translates significantly less to contact with the acromion compared to all other configurations (p < .000 for all comparisons; i.e. 35°: "normal" 8,1 mm (± 0,0) versus "B1" 11,9 mm (± 0,0) versus "B1 Acromion Correction" 12,2 mm (± 0,2) versus "B1 Glenoid Correction" 13,3 mm (± 0,1)). Restoration of normal translation was only achieved with correction of glenoid and acromial anatomy (i.e. 75°: "normal" 11 mm (± 0,8) versus "B1 Acromion Correction" 17,5 mm (± 0,1) versus "B1 Glenoid Correction" 19,7 mm (± 1,3) versus "B1 Glenoid + Acromion Correction" 11,5 mm (± 1,1)). CONCLUSIONS: Persistence or recurrence of static/dynamic posterior instability after correction of glenoid version alone may be related to incomplete restoration of the intrinsic stability that is conferred by a normal acromial anatomy. LEVEL OF EVIDENCE V: biomechanical study.
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INTRODUCTION: There is a lack of gender-specific research after reverse total shoulder arthroplasty (RTSA). Although previous studies have documented worse outcomes in women, a more thorough understanding of why outcomes may differ is needed. We therefore asked: (1) Are there gender-specific differences in preoperative and postoperative clinical scores, complications, surgery-related parameters, and demographics? (2) Is female gender an independent risk factor for poorer clinical outcomes after RTSA? (3) If so, why is female gender associated with poorer outcomes after RTSA? MATERIALS AND METHODS: Between 2005 and 2019, 987 primary RTSAs were performed in our institution. After exclusion criteria were applied, data of 422 female and 271 male patients were analyzed. Clinical outcomes (absolute/relative Constant Score [a/rCS] and Subjective Shoulder Value [SSV]), complications (intra- and/or postoperative fracture, loosening), surgery-related parameters (indication, implant-related characteristics), and demographics (age, gender, body mass index, and number of previous surgeries) were evaluated. Preoperative and postoperative radiographs were analyzed (critical shoulder angle, deltoid-tuberosity index, reverse shoulder angle, lateralization shoulder angle, and distalization shoulder angle). RESULTS: Preoperative clinical scores (aCS, rCS, SSV, and pain level) and postoperative clinical outcomes (aCS and rCS) were significantly worse in women. However, the improvement between preoperative and postoperative outcomes was significantly higher in female patients for rCS (P = .037), internal rotation (P < .001), and regarding pain (P < .001). Female patients had a significantly higher number of intraoperative and postoperative fractures (24.9% vs. 11.4%, P < .001). The proportion of female patients with a deltoid-tuberosity index <1.4 was significantly higher than males (P = .01). Female gender was an independent negative predictor for postoperative rCS (P = .047, coefficient -0.084) and pain (P = .017, coefficient -0.574). In addition to female sex per se being a predictive factor of worse outcomes, females were significantly more likely to meet 2 of the 3 most significant predictive factors: (1) significantly worse preoperative clinical scores and (2) higher rate of intra- and/or postoperative fractures. CONCLUSIONS: Female sex is a very weak, but isolated, negative predictive factor that negatively affects the objective clinical outcome (rCS) after RTSA. However, differences did not reach the minimal clinically important difference, and it is not a predictor for the subjective outcome (SSV). The main reason for the worse outcome in female patients seems to be a combination of higher preoperative disability and higher incidence of fractures. To improve the outcome of women, all measures that contribute to the reduction of perioperative fracture risk should be used.
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CASE: A 40-year-old man presented with progressive shoulder pain, associated with static posterior subluxation and mild eccentric glenohumeral osteoarthritis. Compared with a mean statistical shape model of a normal shoulder, the patient's acromion was abnormally high and horizontal, and the glenoid abnormally inclined inferiorly and minimally retroverted. Restoration of normal scapular anatomy using 3-dimensional planned acromial and glenoid osteotomies led to recentering of the joint and full shoulder function up to 24 months postoperatively. CONCLUSION: The correction of associated acromial and glenoid malformation can revert early static posterior subluxation of the shoulder. Whether successful recentering prevents progression of osteoarthritis remains to be established.
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PURPOSE: Functional internal rotation (IR) is a combination of extension and IR. It is clinically often limited after reverse total shoulder arthroplasty (RTSA) either due to loss of extension or IR in extension. It was the purpose of this study to determine the ideal in-vitro combination of glenoid and humeral components to achieve impingement-free functional IR. METHODS: RTSA components were virtually implanted into a normal scapula (previously established with a statistical shape model) and into a corresponding humerus using a computer planning program (CASPA). Baseline glenoid configuration consisted of a 28 mm baseplate placed flush with the posteroinferior glenoid rim, a baseplate inclination angle of 96° (relative to the supraspinatus fossa) and a 36 mm standard glenosphere. Baseline humeral configuration consisted of a 12 mm humeral stem, a metaphysis with a neck shaft angle (NSA) of 155° (+ 6 mm medial offset), anatomic torsion of -20° and a symmetric PE inlay (36mmx0mm). Additional configurations with different humeral torsion (-20°, + 10°), NSA (135°, 145°, 155°), baseplate position, diameter, lateralization and inclination were tested. Glenohumeral extension of 5, 10, 20, and 40° was performed first, followed by IR of 20, 40, and 60° with the arm in extension of 40°-the value previously identified as necessary for satisfactory clinical functional IR. The different component combinations were taken through simulated ROM and the impingement volume (mm3) was recorded. Furthermore, the occurrence of impingement was read out in 5° motion increments. RESULTS: In all cases where impingement occurred, it occurred between the PE inlay and the posterior glenoid rim. Only in 11 of 36 combinations full functional IR was possible without impingement. Anterosuperior baseplate positioning showed the highest impingement volume with every combination of NSA and torsion. A posteroinferiorly positioned 26 mm baseplate resulting in an additional 2 mm of inferior overhang as well as 6 mm baseplate lateralization offered the best impingement-free functional IR (5/6 combinations without impingement). Low impingement potential resulted from a combination of NSA 135° and + 10° torsion (4/6 combinations without impingement), followed by NSA 135° and -20° torsion (3/6 combinations without impingement) regardless of glenoid setup. CONCLUSION: The largest impingement-free functional IRs resulted from combining a posteroinferior baseplate position, a greater inferior glenosphere overhang, 90° of baseplate inclination angle, 6 mm glenosphere lateralization with respect to baseline setup, a lower NSA and antetorsion of the humeral component. Surgeons can employ and combine these implant configurations to achieve and improve functional IR when planning and performing RTSA. LEVEL OF EVIDENCE: Basic Science Study, Biomechanics.
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PURPOSE: Posttraumatic fibular malunion alters ankle joint biomechanics and may lead to pain, stiffness, and premature osteoarthritis. The accurate restoration is key for success of reconstructive surgeries. The aim of this study was to analyze the accuracy of a novel three-dimensional (3D) registration algorithm using different segments of the contralateral anatomy to restore the distal fibula. METHODS: Triangular 3D surface models were reconstructed from computed tomographic data of 96 paired lower legs. Four segments were defined: 25% tibia, 50% tibia, 75% fibula, and 75% fibula and tibia. A surface registration algorithm was used to superimpose the mirrored contralateral model on the original model. The accuracy of distal fibula restoration was measured. RESULTS: The median rotation error, 3D distance (Euclidean distance), and 3D angle (Euler's angle) using the distal 25% tibia segment for the registration were 0.8° (- 1.7-4.8), 2.1 mm (1.4-2.9), and 2.9° (1.9-5.4), respectively. The restoration showed the highest errors using the 75% fibula segment (rotation error 3.2° (0.1-8.3); Euclidean distance 4.2 mm (3.1-5.8); Euler's angle 5.8° (3.4-9.2)). The translation error did not differ significantly between segments. CONCLUSION: 3D registration of the contralateral tibia and fibula reliably approximated the premorbid anatomy of the distal fibula. Registration of the 25% distal tibia, including distinct anatomical landmarks of the fibular notch and malleolar colliculi, restored the anatomy with increasing accuracy, minimizing both rotational and translational errors. This new method of evaluating malreductions could reduce morbidity in patients with ankle fractures. LEVEL OF EVIDENCE: IV.
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The benefit of protective bracing after rotator cuff reconstruction has been debated for many years, although immobilization compliance has never been assessed objectively to date. In a previous study, compliance with the wearing of an abduction brace was measured for the first time with use of temperature-sensitive sensors. The purpose of the present follow-up study was to assess the effect of immobilization compliance on tendon-healing after rotator cuff repair. Methods: The clinical and radiographic outcomes for 46 consecutive patients with objectively assessed abduction brace wearing compliance after arthroscopic repair of a superior rotator cuff tear were prospectively analyzed. Rotator cuff integrity was examined with ultrasound. Clinical outcomes were assessed with the relative Constant-Murley score (RCS), the Subjective Shoulder Value (SSV), and pain and patient satisfaction ratings. Receiver operating characteristic (ROC) curves were used to determine the optimal cutoff value of abduction brace compliance for discriminating between shoulders that will and will not have a retear and the association of compliance with the failure of rotator cuff repair. Results: After a mean duration of follow-up of 20 ± 9 months, the odds ratio for having a rotator cuff repair failure was 13-fold higher for patients with a compliance rate of <60% (p = 0.037). The retear rate was 3% (1 of 35 patients) in the high-compliance cohort (≥60% compliance) and 27% (3 of 11) in the low-compliance cohort (<60% compliance) (p = 0.037). No differences in RCS, SSV, pain, or postoperative patient satisfaction were observed between patients with ≥60% compliance and those with <60% compliance. Conclusions: Patients with a compliance rate of <60% had a 13-fold increase in the risk of rotator cuff retear. The 2 patients with the lowest compliance rates (11% and 22%) both had retears. Due to the small sample size, no final conclusions can be drawn regarding the influence of immobilization compliance on tendon-healing after rotator cuff repair. These findings justify a prospective trial with a larger cohort to confirm or disprove the value of compliance with abduction bracing. Level of Evidence: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.
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BACKGROUND: Disabling loss of functional internal rotation (fIR) after reverse total shoulder arthroplasty (RTSA) is frequent but not well understood. This study tested the hypothesis that limitation of fIR after RTSA is not primarily related to a deficit in internal rotation. METHODS: Fifty patients (mean age at RTSA, 74 ± 11.7 years) who were consecutively seen at a yearly follow-up visit at 1-10 years (median, 4 years) after RTSA were prospectively examined with special attention to fIR. Patients with axillary nerve or deltoid dysfunction were excluded. Relative (age- and sex-adjusted) Constant-Murley scores (CSs) and Subjective Shoulder Values were assessed preoperatively and at final follow-up. In addition, active extension and 4 postoperative activities of daily living (ADLs) requiring fIR were tested at follow-up. Rotator cuff fatty infiltration and notching were evaluated radiographically. For analysis, patients were divided into a group with poor fIR (fIR-, n = 19), defined as ≤2 internal-rotation points in the CS, and a group with good fIR (fIR+, n = 31), defined as ≥4 internal-rotation points in the CS. RESULTS: Active extension of the contralateral shoulders was comparable in the fIR- group (mean, 60.3° [standard deviation (SD), 11.2°]) and fIR+ group (66.1° [SD, 14.2°]). Postoperatively, a difference in active extension between the unaffected and operated sides was present in both groups and averaged 16° (55° [SD, 14.3°] in fIR+ group and 39.1° [SD, 10.8°] in fIR- group; P < .001). No patient in the fIR+ group had active extension < 40° (range, 40°-85°). Shoulders with extension ≥ 40° but unsatisfactory fIR had restricted passive internal rotation in extension. The ability to perform ADLs behind the back correlated better with shoulder extension than with so-called fIR measurements in the CS. CONCLUSION: Functional internal rotation after RTSA requires at least 40° of shoulder extension. If fIR is unsatisfactory despite 40° of extension, passive restriction of internal rotation in full extension is the limiting factor. It is crucial to preserve or restore active shoulder extension to allow ADLs involving internal rotation.
Subject(s)
Arthroplasty, Replacement, Shoulder , Rotator Cuff Injuries , Shoulder Joint , Activities of Daily Living , Humans , Range of Motion, Articular , Retrospective Studies , Rotator Cuff Injuries/surgery , Shoulder/surgery , Shoulder Joint/surgery , Treatment OutcomeABSTRACT
PURPOSE: The purpose of this study was to describe the medial and lateral posterior tibial slope (MPTS and LPTS) on 3D-CT in a Caucasian population without osteoarthritis. It was hypothesised that standard TKA alignment techniques would not reproduce the anatomy in a high percentage of native knees. METHODS: CT scans of 301 knees [male:female = 192:109; mean age 30.1 ([Formula: see text] 6.1)] were analysed retrospectively. Tibial slope was measured medially and laterally in relation to the mechanical axis of the tibia. The proportion of MPTS and LPTS was calculated, corresponding to the "standard PTS" of 3°-7°. The proportion of knees accurately reproduced with the recommended PTS of 0°-3° for PS and 5°-7° for CR TKA were evaluated. RESULTS: Interindividual mean values of MPTS and LPTS did not differ significantly (mean (range); MPTS: 7.2° ( - 1.0°-19.0°) vs. LPTS: 7.2° ( - 2.4°-17.8°), n.s.). The mean absolute intraindividual difference was 2.9° (0.0°-10.8°). In 40.5% the intraindividual difference between MPTS and LPTS was > 3°. When the standard slope of 3°-7° medial and lateral was considered, only 15% of the knees were covered. The tibial cut for a PS TKA or a CR TKA changes the combined PTS (MPTS + LPTS) in 99.3% and 95.3% of cases, respectively. CONCLUSION: A high interindividual range of MPTS and LPTS as well as considerable intraindividual differences were shown. When implementing the recommended slope values for PS and CR prostheses, changes in native slope must be accepted. Further research is needed to evaluate the impact of altering a patient's native slope on the clinical outcome. LEVEL OF EVIDENCE: IV.
Subject(s)
Arthroplasty, Replacement, Knee , Osteoarthritis, Knee , Adult , Arthroplasty, Replacement, Knee/methods , Female , Humans , Knee Joint/diagnostic imaging , Knee Joint/surgery , Male , Osteoarthritis, Knee/diagnostic imaging , Osteoarthritis, Knee/surgery , Retrospective Studies , Tibia/anatomy & histology , Tibia/diagnostic imaging , Tibia/surgeryABSTRACT
PURPOSE: Glenohumeral osteoarthritis (OA) represents a challenging problem in young, physically active patients. It was the purpose of this investigation to evaluate the results of a pilot study involving glenoid resurfacing with a glenoid allograft combined with a hemiarthroplasty on the humeral side. METHODS: Between April 2011 to November 2013, 5 patients (3 men, 2 women, mean age 46.4, range 35-57) with advanced OA of the glenohumeral joint, were treated with a humeral head replacement combined with replacement of the glenoid surface with an osteochondral, glenoid allograft. RESULTS: Overall, clinically, there was one excellent, one satisfactory and three poor results. Mean preoperative subjective shoulder value (SSV) was 34% (range: 20-50%) and preoperative relative Constant-Murley-Score (CSr) was 43 points (range: 29-64 points). Three patients with poor results had to be revised within the first three years. Their mean pre-revision SSV and CSr were 38% (range: 15-80%) and 36 points (range: 7-59 points) respectively. One patient was revised 9 years after the primary procedure with advanced glenoid erosion and pain and one patient has an ongoing satisfactory outcome without revision. Their SSVs were 60% and 83%, their CSr were 65 points and 91 points, 9 and 10 years after the primary procedure, respectively. Mean follow-up was 7 years (2-10 years) and mean time to revision was 4 years (range: 1-9 years). CONCLUSION: The in-vivo pilot study of a previously established in-vitro technique of osteochondral glenoid allograft combined with humeral HA led to three early failures and only one really satisfactory clinical outcome which, however, was associated with advanced glenoid erosion. Osteochondral allograft glenoid resurfacing was associated with an unacceptable early failure rate and no results superior to those widely documented for HA or TSA, so that the procedure has been abandoned. LEVEL OF EVIDENCE: Level IV, Case Series, Treatment Study.