Werner Anderl

All-Arthroscopic Implant-Free Iliac Crest Bone Grafting: New Technique and Case Report

Glenoid bone loss is a recognized risk for recurrent instability. Open J-graft augmentation has been reported as a well-established procedure for anterior shoulder instability. Few data are available on arthroscopic techniques for the repair of bony Bankart lesions. We describe an all-arthroscopic implant-free iliac crest bone grafting technique and present the case of a 32-year-old hockey player who underwent glenoid reconstruction using this novel arthroscopic repair technique after 2 failed soft-tissue procedures. After 13 months, the patient reached nearly full range of motion with a slight loss of external rotation. The computed tomography scan showed a restoration of the glenoid cavity and complete healing of the graft.

Erratum to: Patient-specific instrumentation improved mechanical alignment, while early clinical outcome was comparable to conventional instrumentation in TKA

Purpose The aim of this prospective study was to compare early clinical outcome, radiological limb alignment, and three-dimensional (3D)-component positioning between conventional and computed tomography (CT)-based patient-specific instrumentation (PSI) in primary mobile-bearing total knee arthroplasty (TKA).

Arthroscopic Implant-Free Bone Grafting for Shoulder Instability With Glenoid Bone Loss Clinical and Radiological Outcome at a Minimum 2-Year Follow-up

Background: Posttraumatic anteroinferior shoulder dislocations with concomitant glenoid bone loss show high recurrence rates. The open J-bone graft technique for implant-less anatomic restoration of bony glenoid structure has previously been described, whereas results of arthroscopic techniques are currently not available. Purpose: To evaluate clinical and radiological outcome after arthroscopic anatomic reconstruction of the glenoid for recurrent anteroinferior glenohumeral instability. Study Design: Case series; Level of evidence, 4. Methods: Fifteen shoulders of 14 patients with recurrent anteroinferior shoulder instability were prospectively followed after glenoid reconstruction with a modified arthroscopic, implant-free J-bone graft. Preoperatively, the instability severity index score was documented. Patients were followed for a minimum of 2 years using the Rowe score and the Constant score. Subjective outcome was assessed using a visual analog scale (VAS) for pain and the subjective shoulder value for sports (SSVS); satisfaction with procedure outcome was also rated. Range of motion was recorded. Incidence of recurrent instability, defined as dislocation, subluxation, or persistent apprehensiveness, was documented. Pre- and postoperative (1 day and 3, 12, and 24 months) computed tomographic images were used to evaluate glenoid bone loss, reconstruction of the glenoid, and graft remodeling. Results: All preoperative scores (Rowe score: 57.6 ± 14.4; Constant score: 70.9 ± 8.9; VAS: 4.4 ± 2.6; SSVS: 31.4% ± 19.5%) were significantly (P ≤ .02) improved at final follow-up (Rowe score: 98.6 ± 1.5; Constant score: 96.3 ± 3.9; VAS: 0.2 ± 0.6; SSVS: 95.6% ± 3.8%). The preoperative glenoid area (82.1% ± 4.5%) was significantly increased immediately after surgery to 99.2% ± 6.6% (P < .001). After a physiological remodeling process, the glenoid area remained significantly increased at the latest follow-up (89.5 ± 3.2%, P < .001). J-bone grafting successfully restored glenoid concavity by significantly increasing concavity extent and depth from preoperative (19.8 ± 2.1 and 0.9 ± 0.6 mm, respectively) to postoperative (24.0 ± 2.1 and 2.1 ± 0.8 mm, respectively) (P < .001). There were no recurrent instabilities. One traumatic graft fracture occurred during the follow-up period. Conclusion: The arthroscopic J-bone graft technique permits minimally invasive reconstruction of anteroinferior glenoid defects and provided excellent early clinical outcome without recurrent instability in posttraumatic shoulder dislocations. A physiological remodeling process leads to restoration of a more natural glenoid anatomy.

Longitudinal Long-term Magnetic Resonance Imaging and Clinical Follow-up After Single-Row Arthroscopic Rotator Cuff Repair: Clinical Superiority of Structural Tendon Integrity

Background: The number of arthroscopic rotator cuff surgeries is consistently increasing. Although generally considered successful, the reported number of retears after rotator cuff repair is substantial. Short-term clinical outcomes are reported to be rarely impaired by tendon retears, whereas to our knowledge, there is no study documenting long-term clinical outcomes and tendon integrity after arthroscopic rotator cuff repair. Purpose: To investigate longitudinal long-term repair integrity and clinical outcomes after arthroscopic rotator cuff reconstruction. Study Design: Case series; Level of evidence, 4. Methods: Thirty patients who underwent arthroscopic rotator cuff repair with suture anchors for a full-tendon full-thickness tear of the supraspinatus or a partial-tendon full-thickness tear of the infraspinatus were included. Two and 10 years after initial arthroscopic surgery, tendon integrity was analyzed using magnetic resonance imaging (MRI). The University of California, Los Angeles (UCLA) score and Constant score as well as subjective questions regarding satisfaction with the procedure and return to normal activity were used to evaluate short- and long-term outcomes. Results: At the early MRI follow-up, 42% of patients showed a full-thickness rerupture, while 25% had a partial rerupture, and 33% of tendons remained intact. The 10-year MRI follow-up (129 ± 11 months) showed 50% with a total rerupture, while the other half of the tendons were partially reruptured (25%) or intact (25%). The UCLA and Constant scores significantly improved from preoperatively (UCLA total: 50.6% ± 20.2%; Constant total: 44.7 ± 10.5 points) to 2 years (UCLA total: 91.4% ± 16.0% [P < .001]; Constant total: 87.8 ± 15.3 points [P < .001]) and remained significantly higher after 10 years (UCLA total: 89.7% ± 15.9% [P < .001]; Constant total: 77.5 ± 15.6 points [P < .001]). The Constant total score and Constant strength subscore, but not the UCLA score, were also significantly better at 10 years postoperatively in patients with intact tendons compared with patients with retorn tendons (Constant total: 89.0 ± 7.8 points vs 75.7 ± 14.1 points, respectively [P = .034]; Constant strength: 18.0 ± 4.9 points vs 9.2 ± 5.2 points, respectively [P = .006]). The majority of patients rated their satisfaction with the procedure as “excellent” (83.3%), and 87.5% returned to their normal daily activities. Conclusion: Arthroscopic rotator cuff repair showed good clinical long-term results despite a high rate of retears. Nonetheless, intact tendons provided significantly superior clinical long-term outcomes, making the improvement of tendon healing and repair integrity important goals of future research efforts.

The effect of intravenous tranexamic acid on blood loss and early post-operative pain in total shoulder arthroplasty

Aims The purpose of the present study was to evaluate the impact of intravenous tranexamic acid on the reduction of blood loss, transfusion rate, and early post‐operative clinical outcome in total shoulder arthroplasty. Patients and Methods A randomised, placebo‐controlled trial which included 54 patients undergoing unilateral primary stemless anatomical or stemmed reverse total shoulder arthroplasty was undertaken. Patients received either 100 ml saline (placebo, n = 27), or 100 ml saline together with 1000 mg of tranexamic acid (TXA, n = 27) intravenously prior to skin incision and during wound closure. Peri‐operative blood loss via an intra‐articular drain was recorded and total blood loss was calculated. The post‐operative transfusion rate was documented. Assessment of early clinical parameters included the visual analogue scale for pain (VAS), documentation of haematoma formation and adverse events. Results Mean peri‐operative blood drainage (placebo: 170 ml versus TXA: 50 ml, p = 0.001) and calculated mean total blood loss (placebo: 1248.2 ml versus TXA: 871.0 ml, p = 0.009) were significantly lower in the TXA group. No transfusions were necessary during the study period in either group. Mean VAS for pain significantly decreased from pre‐operative (VAS 7) to the early post‐operative period (VAS 1.7, p < 0.001). Significant differences regarding mean post‐operative pain between placebo (VAS 2.0) and TXA (VAS 1.3) were detected (p = 0.05). The occurrence of haematomas was significantly more frequent in the placebo (59.3%, n = 16) than in the TXA group (25.9%, n = 6, p = 0.027). Whereas only mild haematomas developed in the TXA group, in the placebo group a total of 22.2% (n = 6) developed either moderate or severe haematomas. No adverse events associated with administration of TXA occurred. Conclusion Intravenous administration of TXA successfully reduced mean peri‐operative blood drainage, total estimated blood loss, pain during the first post‐operative days, and haematoma formation in total shoulder arthroplasty.

Critical shoulder angle combined with age predict five shoulder pathologies: a retrospective analysis of 1000 cases

BackgroundAcromial morphology has previously been defined as a risk factor for some shoulder pathologies. Yet, study results are inconclusive and not all major shoulder diseases have been sufficiently investigated. Thus, the aim of the present study was to analyze predictive value of three radiological parameters including the critical shoulder angle, acromion index, and lateral acromion angle in relationship to symptomatic patients with either cuff tear arthropathy, glenohumeral osteoarthritis, rotator cuff tear, impingement, and tendinitis calcarea.MethodsA total of 1000 patients’ standardized true-anteroposterior radiographs were retrospectively assessed. Receiver-operating curve analyses and multinomial logistic regression were used to examine the association between shoulder pathologies and acromion morphology. The prediction model was derived from a development cohort and applied to a validation cohort. Prediction model’s performance was statistically evaluated.ResultsThe majority of radiological measurements were significantly different between shoulder pathologies, but the critical shoulder angle was an overall better parameter to predict and distinguish between the different pathologies than the acromion index or lateral acromion angle. Typical critical shoulder angle-age patterns for the different shoulder pathologies could be detected. Patients diagnosed with rotator cuff tears had the highest, whereas patients with osteoarthritis had the lowest critical shoulder angle. The youngest patients were in the tendinitis calcarea and the oldest in the cuff tear arthropathy group.ConclusionsThe present study showed that critical shoulder angle and age, two easily assessable variables, adequately predict different shoulder pathologies in patients with shoulder complaints.

Biomechanical Evaluation of Glenoid Reconstruction With an Implant-Free J-Bone Graft for Anterior Glenoid Bone Loss

Background: The anatomic restoration of glenoid morphology with an implant-free J-shaped iliac crest bone graft offers an alternative to currently widely used glenoid reconstruction techniques. No biomechanical data on the J-bone grafting technique are currently available. Purpose: To evaluate (1) glenohumeral contact patterns, (2) graft fixation under cyclic loading, and (3) the initial stabilizing effect of anatomic glenoid reconstruction with the implant-free J-bone grafting technique. Study Design: Controlled laboratory study. Methods: Eight fresh-frozen cadaveric shoulders and J-shaped iliac crest bone grafts were used for this study. J-bone grafts were harvested, prepared, and implanted according to a previously described, clinically used technique. Glenohumeral contact patterns were measured using dynamic pressure-sensitive sensors under a compressive load of 440 N with the humerus in (a) 30° of abduction, (b) 30° of abduction and 60° of external rotation, (c) 60° of abduction, and (d) 60° of abduction and 60° of external rotation. Using a custom shoulder-testing system allowing positioning with 6 degrees of freedom, a compressive load of 50 N was applied, and the peak force needed to translate the humeral head 10 mm anteriorly at a rate of 2.0 mm/s was recorded. All tests were performed (1) for the intact glenoid, (2) after the creation of a 30% anterior osseous glenoid defect parallel to the longitudinal axis of the glenoid, and (3) after anatomic glenoid reconstruction with an implant-free J-bone graft. Furthermore, after glenoid reconstruction, each specimen was translated anteriorly for 5 mm at a rate of 4.0 mm/s for a total of 3000 cycles while logging graft protrusion and mediolateral bending motions. Graft micromovements were recorded using 2 high-resolution, linear differential variable reluctance transducer strain gauges placed in line with the long leg of the graft and the mediolateral direction, respectively. Results: The creation of a 30% glenoid defect significantly decreased glenohumeral contact areas (P < .05) but significantly increased contact pressures at all abduction and rotation positions (P < .05). Glenoid reconstruction restored the contact area and contact pressure back to levels of the native glenohumeral joint in all tested positions. The mean (±SD) force to translate the humeral head anteriorly for 10 mm (60° of abduction: 31.7 ± 12.6 N; 60° of abduction and 60° of external rotation: 28.6 ± 7.6 N) was significantly reduced after the creation of a 30% anterior bone glenoid defect (60° of abduction: 12.2 ± 6.8 N; 60° of abduction and 60° of external rotation: 11.4 ± 5.4 N; P < .001). After glenoid reconstruction with a J-bone graft, the mean peak translational force significantly increased (60° of abduction: 85.0 ± 8.2 N; 60° of abduction and 60° of external rotation: 73.6 ± 4.5 N; P < .001) compared with the defect state and baseline. The mean total graft protrusion under cyclical translation of the humeral head over 3000 cycles was 138.3 ± 169.8 µm, whereas the mean maximal mediolateral graft deflection was 320.1 ± 475.7 µm. Conclusion: Implant-free anatomic glenoid reconstruction with the J-bone grafting technique restored near-native glenohumeral contact areas and pressures, provided secure initial graft fixation, and demonstrated excellent osseous glenohumeral stability at time zero. Clinical Relevance: The implant-free J-bone graft is a viable alternative to commonly used glenoid reconstruction techniques, providing excellent graft fixation and glenohumeral stability immediately postoperatively. The normalization of glenohumeral contact patterns after reconstruction could potentially avoid the progression of dislocation arthropathy.

An Arthroscopic Knotless Technique for Anatomical Restoration of the Rotator Cuff and Superior Capsule: The Double-Layer Cinch Bridge

Rotator cuff repairs are the most common procedures in shoulder surgery, but still show long-term retear rates of up to 70%. Nonanatomic reconstruction is one possible cause of repair failure. The rotator cuff histologically consists of 5 separate layers of which 2 are macroscopically identifiable: the superior or tendinous layer and the inferior or capsule-ligamentous layer. In case of rotator cuff tears, these layers are often retracted to different degrees. The intraoperative detectable prevalence of rotator cuff delamination reaches up to 85%. Anatomical rotator cuff repair, which also includes restoration of the layered structure, could re-establish native tendon morphology and thus potentially decreases retear rates. The use of a knotless construct to avoid cuff strangulation and maintaining tendon perfusion could further decrease the risk of repair failure. Double-layer reconstructions are challenging and time consuming because each layer needs to be penetrated separately. Only few studies reported about double-layer reconstruction of the posterosuperior rotator cuff. This Technical Note is the first to present an arthroscopic knotless transosseous-equivalent double-layer repair technique.

Double-Layer Rotator Cuff Repair: Anatomic Reconstruction of the Superior Capsule and Rotator Cuff Improves Biomechanical Properties in Repairs of Delaminated Rotator Cuff Tears.

Background: Delamination in rotator cuff tears has been identified as a prognostic factor for negative outcome after repair, with a reported prevalence between 38% and 88%. Purpose: To compare biomechanical properties of 3 repair techniques for delaminated rotator cuff tears. Study Design: Controlled laboratory study. Methods: Eighteen fresh-frozen cadaveric shoulders were used to evaluate rotator cuff footprint reconstruction, contact area and pressure, displacement under cyclical loading, and load to failure of 3 double-row repair configurations: double-row suture repair with medial row knots (medially knotted bridge, mkB); knotless double-row repair using suture tapes (knotless bridge, klB); and knotless double-row, double-layer-specific repair (double-layer, DL). Dynamic pressure sensors were used to assess contact patterns at the footprint region in 0°, 30°, and 60° of glenohumeral abduction and 5 rotational positions (0°, 30° of internal rotation, 30° of external rotation, 60° of internal rotation, 60° of external rotation). Optical markers were used to document whole tendon and individual layer displacement after rotator cuff repair under cyclical loading for 200 cycles (10 N to 100 N at 1 Hz). Specimens were then loaded monotonically to failure at a rate of 33 mm/min. Results: Mean contact area and footprint restoration were highest in the DL group at 60° of glenohumeral abduction for all rotational positions (mkB mean ± SD, 195.4 ± 54.3 mm2, 66.7% ± 19.7%; klB, 250.6 ± 34.9 mm2, 76.2% ± 10.3%; DL, 318.4 ± 36.6 mm2, 109.1% ± 24.0%; P < .001). The double-layer-specific repair showed the least displacement under cyclical loading (mkB mean ± SD, 0.53 ± 0.18 mm; klB, 0.79 ± 0.37 mm; DL, 0.31 ± 0.24 mm; P = .029), most closely resembling the native tendon. Peak loads at failure were comparable between repair groups (mkB mean ± SD, 366.92 ± 70.59 N; klB, 280.05 ± 77.66 N; DL, 398.35 ± 109.04 N; P = .083). Conclusion: Anatomic restoration of the superior capsular and tendon insertion in delaminated rotator cuff tears with a double-layer-specific repair configuration demonstrated superior footprint restoration with increasing abduction, while providing construct displacement comparable to the native tendon under cyclical loading. Peak load at failure was comparable between repair constructs. Clinical Relevance: The prevalence and clinical importance of delaminated rotator cuff tears have long been underestimated. Anatomically correct individual reconstruction of the superior capsule and rotator cuff could restore near-native biomechanics and potentially reduce the risk of rotator cuff repair failure.

Arthroscopic Treatment Options for Glenohumeral Osteoarthritis

Osteoarthritis (OA) of the shoulder is a chronic, progressive, and multifactorial disease characterized by degenerative and inflammatory processes affecting the glenohumeral joint. The incidence of primary OA has been reported as approximately 5 % of patients with shoulder complaints. Although OA in the shoulder is less common than OA of the knee or hip, OA can cause severe pain and dysfunction of the shoulder. Pathologic changes in shoulder OA involve the progressive breakdown of the articular cartilage within the glenohumeral joint starting with narrowing of the joint space and fibrillation of the surface, followed by osteochondral lesions, osteophyte formations, labrum degradation, capsular tightness, and inflammation. As OA may also affect supporting structures such as muscles, tendons, and ligaments, shoulder joint degeneration can also be linked to secondary causes such as rotator cuff tendon tears, shoulder instability especially in young patients, and trauma.