Salvage Algorithm for Deep Surgical Site Infections after HTO with Unstable Bone Situation Using a Hexapod System - Primary Results.

The incidence of deep surgical site infections following high tibial osteotomy (HTO) ranges between 0.4 to 4.7%. It is a severe complication with a high risk for poor clinical outcome. The aim of this study was to proof that a salvage algorithm for infected HTO with unstable bone situation leads to an infection-free status and bone union of the osteotomy and that correct limb alignment can be restored with good knee function.The study included seven patients with peri-implant infections following HTO. Infections occurred 83 ± 58.9 days (range: 24-191) after HTO. All patients underwent the "RESTORE" algorithm: patients received (1) REmoval of the HTO hardware and extensive debridement; (2) the osteotomy was STabilized with a hexapod external fixator (Taylor Spatial Frame, TSF); (3) the osteotomy gap was Opened; and (4) the alignment was REconstructed using the TSF, aiming for the intended limb alignment of the initial HTO. Patient-reported outcomes were assessed 22-36 months after removal of the TSF.After 24 weeks (range: 11-35), an infection-free status and bone healing were achieved. In all cases, the limb was saved, and the previously targeted mechanical axis of the lower limb was restored. All patients reached full extension of the knee joint and at least 110° of flexion. For KOOS: Symptoms 67.86 ± 18.1, Pain 73.41 ± 16.58, ADL 78.99 ± 21.32, Sports 52.14 ± 25.96, and QoL 41.96 ± 24.66. OKS 35.71 ± 8.8, SF-12 Physical Health 38.89 ± 10.3, and SF-12 Mental Health 46.86 ± 13.76.The "RESTORE" algorithm is a safe and effective salvage procedure. The concept allows for saving the limb and obtaining the previously planned limb alignment. Patient-reported outcome measures showed slightly lowered values than healthy samples, but substantially better values than patients awaiting HTO. Due to the possibility of initial full weight-bearing, the risk of higher morbidity caused by immobilization is minimized.

Classification and Incidence of Heterotopic Ossifications in Relation to NSAID Prophylaxis after Elbow Trauma.

Heterotopic ossification (HO) after elbow trauma can be responsible for significant motion restrictions. The study's primary aim was to develop a new X-ray-based classification for HO of the elbow. This retrospective study analyzed elbow injury radiographs from 138 patients aged 6-85 years (mean 45.9 ± 18) who underwent operative treatment. The new classification was applied at 6 weeks, 12 weeks, and 6 months postoperatively. The severity of HO was graded from 0 to 4 and localization was defined as r (radial), p (posterior), u (ulnar) or a (anterior) by two observers. The patients were categorized based on injury location and use of non-steroidal anti-inflammatory drugs (NSAIDs) for HO prophylaxis. The correlations between the generated data sets were analyzed using Chi-square tests (χ2) with a significance level of p < 0.05. The inter- and intraobserver reliability was assessed using Cohen's Kappa. In 50.7% of the evaluated X-rays, the formation of HO could be detected after 12 weeks, and in 60% after 6 months. The analysis showed a significant correlation between the injury's location and the HO's location after 12 weeks (p = 0.003). The use of an NSAID prophylaxis did not show a significant correlation with the severity of HO. The classification showed nearly perfect inter- (κ = 0.951, p < 0.001) and intrareliability (κ = 0.946, p < 0.001) according to the criteria of Landis and Koch. Based on the presented classification, the dimension and localization of HO in the X-ray image can be described in more detail compared to previously established classifications and, thus, can increase the comparability of results across studies.

Higher conversion rate to knee arthroplasty in female patients following medial open-wedge high tibial osteotomy.

PURPOSE: Most studies about medial open-wedge high tibial osteotomy (HTO) reported outcomes without focusing on gender differences. Therefore, the study compared the long-term survival rate and postoperative subjective knee function after HTO in female versus male patients with symptomatic medial compartment knee osteoarthritis. METHODS: The data of three cohorts with long-term outcomes were analysed (n = 245; 32% females; age: 49 ± 7 years; Kellgren Lawrence Grade I 6.1%, II 32.7%, III 42.4%; IV 18.8%). The minimum follow-up was at least 6 years or an earlier conversion to total knee arthroplasty (TKA). The gender-specific survival rate after HTO was calculated after 5 and 10 years and compared using Kaplan-Meier analysis and the logrank test. Baseline characteristics and subjective knee function (International Knee Documentation Committee [IKDC]/Lysholm) were analysed between both genders. RESULTS: Forty of 78 (51.3%) women and 41 of 167 men (24.5%) underwent TKA. HTO survival in females was significantly lower (p = 0.0010). The 5- and 10-year survival rates were 85.9% and 62.6% for females and 93.4% and 77.7% for males. In females and males, from preoperative to the last follow-up, the IKDC (43 ± 15 to 58 ± 17; 47 ± 14 to 67 ± 18) and the Lysholm (42 ± 18 to 72 ± 18; 55 ± 22 to 77 ± 23) improved significantly (all p < 0.0001). Females had significantly lower preoperative and postoperative IKDC (p = 0.0438; p = 0.0035) and Lysholm scores (p = 0.0002; p = 0.0323). But the absolute improvements of the IKDC and Lysholm were not significantly different between genders. CONCLUSIONS: Females had higher conversion rates to TKA and lower knee function at the last follow-up. However, preoperative knee function was lower in females and the absolute improvement following HTO was similar for both genders. In general, females benefit from HTO to treat medial knee arthritis, and TKA could be postponed for half of female patients for more than 10 years. However, surgeons must be aware of the described inferior outcomes in females for realistic patient expectation management. LEVEL OF EVIDENCE: Level II.

Postoperative Management of Osteochondral Lesions of the Ankle: A Survey Among German-Speaking Foot and Ankle Surgeons.

OBJECTIVE: To assess the current treatment of osteochondral lesions of the ankle (OCLA) by German-speaking foot and ankle surgeons, focusing on the management of postoperative care and rehabilitation. DESIGN: A questionnaire was created by a panel of 4 experienced foot and ankle surgeons on behalf of the "Clinical Tissue Regeneration" (CTR) working group of the German Society of Orthopaedics and Trauma Surgery (DGOU), and distributed electronically to members of the CTR, participants of the German Cartilage Registry (Knorpelregister DGOU©), and members of 6 German-speaking orthopedics or sports medicine societies. Results were classified depending on the consensus within the answers (agreement ≥75% "strong tendency," 50%-74% "tendency," 25%-49% "weak tendency," <25% "no tendency"). RESULTS: A total of 60 participants returned the questionnaire. The main results are as follows: regarding the frequency of surgical procedures for OCLA, refixation of the fragment, retrograde drilling, and bone marrow stimulation with or without using a matrix were performed by at least 75% of the surgeons and was considered a strong tendency. There was a strong tendency to stabilize the ankle (76.7%) and perform corrective osteotomies (51.7%). In total, 75.5% and 75% of the surgeons performed bone marrow stimulation with and without using a matrix, respectively. Corrective osteotomy and ankle stabilization were performed in 64.5% and 65.2% cases, respectively. Most participants included published recommendations on postoperative rehabilitation and the return to sports activities in their postoperative management. The main surgical procedures were considered the most critical factor in influencing the postoperative management by 81% of the participants (strong tendency). Adjunct surgical procedures such as corrective osteotomy and stabilization of the ankle were considered important by 67.8% of the respondents (tendency). CONCLUSIONS: The management of OCLA varies among German-speaking foot and ankle surgeons. Therefore, guidelines remain essential to standardize the management of OCLA, to achieve improved and stable results. This survey will assist clinicians and patients with rehabilitation to return to sports after treating the ankle's cartilage injury.

Long-term Outcomes after Medial Open Wedge High Tibial Osteotomy - A Retrospective Study of 69 Patients.

High tibial osteotomy (HTO) is a widespread option to avoid or delay total knee arthroplasty (TKA). The present study aimed to assess the long-term survival rate and postoperative subjective knee function after isolated medial open wedge HTO in patients with symptomatic medial compartment knee osteoarthritis (OA) and varus malalignment.Sixty-nine patients (48.8 ± 6.7, 35-66 years; preoperative mechanical tibiofemoral angle [mTFA] -5.3 ± 3.4; -14.9-0.0° varus) treated with medial open wedge HTO using a TomoFix plate were included in this retrospective study, with a follow-up of at least 10 years (11.8 ± 1.0 years). The survival rate after HTO was calculated after 5 and 10 years. Subjective knee function was assessed using Hospital for Special Surgery (HSS), Oxford knee, Lequesne, and Lysholm scores.Thirty-three patients underwent conversion to TKA, on average, 7.0 ± 3.4 (1.3-13.7) years after HTO. Five- and ten-year survival rates were 84.1 and 60.9%, respectively. Patients without conversion to TKA showed a Lysholm score of 64.5 (35-92), Lequesne score of 7 (1-13), HSS score of 71 (56-86), and Oxford knee score of 38.5 (25-44) at the last follow-up (more than 10 years). Significantly higher scores were registered at the last follow-up compared to the preoperative state regarding the Lysholm score (preoperative: 43.5 [12-95]; follow-up: 64.5 [35-92]; p < 0.001). The HSS score (preoperative: 69.5 [43-93]; follow-up: 71 [56-86]; p = 0.6941) showed no statistically significant change during the 10-year follow-up period. The Lequesne score was significantly lower than the preoperative score (preoperative: 11.5 [0.5-22]; follow-up: 7 [1-13]; p < 0.001), indicating a lower handicap.The majority of patients with a valgus medial compartmental knee OA treated with HTO with fixation using the TomoFix plate can expect no conversion to TKA for more than 10 years. Furthermore, patients without conversion to TKA after 10 years still had a significantly higher subjective knee function than preoperatively. Further research is needed to identify risk factors for conversion to TKA. This helps to guide surgeons in selecting patients who will benefit most from HTO.

Etiology, Classification, Diagnostics, and Conservative Management of Osteochondral Lesions of the Talus. 2023 Recommendations of the Working Group "Clinical Tissue Regeneration" of the German Society of Orthopedics and Traumatology.

METHODS: Peer-reviewed literature was analyzed regarding different topics relevant to osteochondral lesions of the talus (OLTs) treatment. This process concluded with a statement for each topic reflecting the best scientific evidence available for a particular diagnostic or therapeutic concept, including the grade of recommendation. Besides the scientific evidence, all group members rated the statements to identify possible gaps between literature and current clinical practice. CONCLUSION: In patients with minimal symptoms, OLT progression to ankle osteoarthritis is unlikely. Risk factors for progression are the depth of the lesion on MRI, subchondral cyst formation, and the extent of bone marrow edema. Conservative management is the adaptation of activities to the performance of the ankle joint. A follow-up imaging after 12 months helps not to miss any progression. It is impossible to estimate the probability of success of conservative management from initial symptoms and imaging. Cast immobilization is an option in OLTs in children, with a success rate of approximately 50%, although complete healing, estimated from imaging, is rare. In adults, improvement by conservative management ranges between 45% and 59%. Rest and restrictions for sports activities seem to be more successful than immobilization. Intra-articular injections of hyaluronic acid and platelet-rich plasma can improve pain and functional scores for more than 6 months. If 3 months of conservative management does not improve symptoms, surgery can be recommended.

Ankle fractures of the geriatric patient: a narrative review.

The present narrative review provides a summary of current concepts for the treatment of ankle fractures in elderly patients. Despite a high complication rate, open reduction and internal fixation is the gold standard for operative care. However, individual patient-based treatment decision considering the soft-tissue status, the fracture pattern, as well as the patient's mobility and comorbidities is mandatory to achieve sufficient patient outcomes. Due to high complication rates after surgery in the past, techniques such as fibular nails or minimal invasive techniques should be considered.

Work intensity and quality of life can be restored following double-level osteotomy in varus knee osteoarthritis.

PURPOSE: The purpose of this study was to assess changes in health-related quality of life (HRQL) and work intensity following double-level knee osteotomy (DLO). It was hypothesized that postoperative HRQL would be comparable to that of the general population and that work intensity can be restored in the short term. METHODS: Twenty-four patients (28 varus knees; mechanical tibiofemoral angle: -11.0 ± 3.0° (-6.0 to -17.0), age: 49.1 ± 9.5 (31-65) years) who underwent DLO were included. The duration the patients were unable to work was evaluated. HRQL was measured with the SF-36 questionnaire, which consists of a physical (PCS) and mental component summary score (MCS). The pre- to postoperative changes in the PCS and MCS were analysed. The PCS and MCS were also compared to those of the general population, who has a reference score value of 50 points. The work intensity measured with the REFA classification and the Tegner activity scale were assessed preoperatively and at the final postoperative follow-up examination (18.0 ± 10.0 (5-43) months). RESULTS: The duration that the patients were unable to work was 12.2 ± 4.4 (6-20) weeks. The PCS improved from 32.1 ± 11.3 (14.5-53.3) preoperatively to 54.6 ± 8.5 (25.2-63.7) (p < 0.001) at the final follow-up, and the MCS improved from 53.9 ± 11.1 (17.1-67.7) to 57.2 ± 3.1 (47.3-61.7) (n.s). The preoperative PCS was significantly lower than the reference score of the general population (p < 0.001), whereas the preoperative MCS was similar between the two groups (n.s.). At follow-up, no significant differences were observed between the PCS and the MCS of the patient group and those of the general population. Five patients who were unable to work prior to surgery due to knee symptoms returned to work with moderate (four patients) or even very heavy (one patient) workloads. The Tegner activity scale increased significantly from a median of 2.0 (0.0-5.0) to 4.0 (2.0-7.0) (p < 0.001). CONCLUSION: Our results demonstrate an improvement in quality of life and return to working activity following DLO in the short term. The HRQL can be improved by DLO in patients with varus knee osteoarthritis to the level of the general population. These results can assist surgeons in discussing realistic expectations when considering patients for DLO. LEVEL OF EVIDENCE: Study type: therapeutic, IV.

Weight-bearing Restrictions after Distal Femur Fractures - Review of Current Literature. / Belastungsvorgaben nach distaler Femurfraktur - eine aktuelle Literaturübersicht.

The incidence of distal femur fractures increases in the geriatric patient. The primary treatment goal in these fractures is early mobilisation to prevent secondary injuries associated with immobility. In light of the increasing spectrum of therapeutic options for postoperative fracture treatment, including double plating, nail-plate combination and distal femur replacement as postoperative treatments, weight-bearing recommendations are becoming increasingly important. The aim of this study was thus to analyse the weight-bearing recommendations and associated therapy results within the literature of the past 9 years and compare the recommendations to our own approach.

Risk of Periprosthetic Joint Infection after Posttraumatic Hip Arthroplasty following Acetabular Fractures.

BACKGROUND: Raised complication rates have been reported for total hip arthroplasty (THA) in posttraumatic hip joints after acetabular fractures with prior open reduction and internal fixation (ORIF). The present study evaluated (I) postoperative surgical site infection and the risk of early infection following THA in posttraumatic hip joints after acetabular fractures and (II) the discriminatory ability of preoperative C-reactive protein (CRP) blood levels for periprosthetic joint infection (PJI). MATERIALS AND METHODS: Patients were included who had undergone THA (2014-2019) after prior ORIF, and nonsurgically treated acetabular fractures. Patients' demographics and the duration between fracture and THA implantation were assessed. Preoperative diagnostic testing (laboratory results, hip aspirations) as well as the results of intraoperative microbiological swabs and sonication were also evaluated. Postoperative complications were recorded. RESULTS: Sixty-seven patients (51 men/16 women) were included, with a mean age of 54.7 ± 14.0 years (range: 18.0-82.9). The mean time between acetabular fracture and THA was 13.5 ± 14.9 years (0.2-53.5). Four subgroups were classified: subgroup I (nonsurgical, n = 15), subgroup II (complete removal of osteosynthesis, n = 8), subgroup III (partial removal of osteosynthesis, n = 15), and subgroup IV (remaining osteosynthesis, n = 29). Preoperative CRP blood levels were normal. CRP levels had no discriminatory ability to predict PJI (AUC: 0.43). Positive microbiological swabs were assessed in subgroups III (n = 1) and IV (n = 2). Complications during follow-up occurred in subgroups I (one aseptic loosening [6.7%]), III (one wound revision [6.7%], two low-grade infections [13.3%]), and IV (three low-grade infections [10.3%]). CONCLUSION: High infection rates were found in patients with THA after acetabular fracture with remaining implants or partial implant removal. Serum CRP alone seems to be a poor predictor. Therefore, an extensive diagnostic algorithm can help to detect an occult infection, including preoperative hip aspiration (microbiological samples and measurements of synovial CRP, WBC, and alpha-defensin levels). Intraoperative tissue samples and sonication results should be obtained during THA implantation.

[MRI case series shows the development of medial gonarthrosis after medial meniscus tear and partial medial meniscectomy]. / Fallbericht zur Entstehung einer medialen Gonarthrose nach Innenmeniskusläsion und erfolgter Teilresektion.

Meniscal injuries lead to changes in pressure distribution in the knee joint. The risk of developing gonarthrosis increases by the amount of resected meniscal tissue. Based on 4 MRI examinations conducted over an 8­year time period, the present case report shows the progress of cartilage degeneration after a traumatic medial meniscus lesion and subsequent partial meniscus resection in a 46-year-old male patient. Congenital or accident-independent risk factors, such as a varus limb deformity must be considered during a medical report.

Os acromiale: prevalence and associated patient-related factors-a population-based study of three thousand and fifty participants.

PURPOSE: The presence of os acromiale is of clinical relevance before performing shoulder surgery but ethnic differences and little information regarding associated factors seem to be present. Population-based studies to clarify these topics are essential so the purpose of this study was to assess the prevalence, anatomy, and associations of os acromiale in a general adult population. METHODS: Both shoulders of 3050 participants from the population-based Study of Health in Pomerania (SHIP) were assessed on magnetic resonance imaging (MRI). Associations with the os acromiale were calculated for sex, age, body height, body weight, and heavy mechanical oscillations on the upper extremity. RESULTS: In total, 1.9% (58/3050) had an os acromiale, while 21 were unilateral left, 23 were unilateral right, and 14 were bilateral. Sixty-eight meso-acromions, three pre-acromions, and one meta-acromion were detected. Os acromiale were more frequent in men (right side: p = 0.037, left side: p = 0.005). Overall, no differences in sides (p = 0.808), to participants' age (right: p = 0.993, left: p = 0.499), body height (right side: p = 0.241, left side: p = 0.154), and the exposure to heavy mechanical oscillations on the upper extremity (right: p = 0.054, left: p = 0.117) were detected. CONCLUSION: Our results support the genetic theory for the aetiology of the os acromiale due to the lower prevalence of the os acromiale in north-eastern Germany compared to the worldwide prevalence (1.9 to 7%) and the lacking association to lifestyle, age, gender, or sides. Additionally, it is important to be aware of possible os acromiale before surgery.

Preexisting and treated concomitant ankle instability does not compromise patient-reported outcomes of solitary osteochondral lesions of the talus treated with matrix-induced bone marrow stimulation in the first postoperative year: data from the German Cartilage Registry (KnorpelRegister DGOU).

PURPOSE: The purpose of this study was to compare the subjective ankle function within the first year following matrix-induced bone marrow stimulation (M-BMS) of patients with a solitary osteochondral lesion of the talus (OCLT) with and without concomitant chronic ankle instability (CAI). METHODS: Data from the German Cartilage Registry (KnorpelRegister DGOU) for 78 patients with a solitary OCLT and a follow-up of at least 6 months were included. All patients received M-BMS for OCLT treatment. The cohort was subdivided into patients with OCLT without CAI treated with M-BMS alone (n = 40) and patients with OCLT and CAI treated with M-BMS and additional ankle stabilisation (n = 38). The Foot and Ankle Ability Measure (FAAM), the Foot and Ankle Outcome Score (FAOS), and the Numeric Rating Scale for Pain (NRS) were used to assess patient-reported outcomes (median (minimum-maximum)). RESULTS: From preoperatively to 12 months postoperatively, patients with OCLT without CAI treated with M-BMS alone had a significant improvement of all subscales in the FAAM [activity of daily living 64.3 (10-100) to 88.1 (39-100); sports 34.4 (0-100) to 65.6 (13-94), functional activities of daily life 50 (0-90) to 80 (30-100), functional sports 30 (0-100) to 70 (5-100)] and FAOS [pain 61.1 (8-94) to 86.1 (50-100), symptoms 60.7 (18-96) to 76.8 (29-100), activities of daily living 72.1 (24-100) to 91.9 (68-100), sport/recreational activities 30.0 (0-70) to 62.5 (0-95), quality of life 31.3 (6-50) to 46.9 (19-100)]. Within the first year, patients with OCLT and CAI treated with M-BMS and ankle stabilisation also showed significant improvement in the FAAM [activity of daily living 68.8 (5-99) to 90.5 (45-100); sports 32.8 (0-87.5) to 64.1 (0-94), functional activities of daily life 62.5 (25-100) to 80 (60-90), functional sports 30 (0-100) to 67.5 (0.95)] and the FAOS [pain 66.7 (28-92) to 87.5 (47-100), symptoms 57.1 (29-96) to 78.6 (50-100), activities of daily living 80.1 (25-100) to 98.5 (59-100), sport/recreational activities 35.0 (0-100) to 70.0 (0-100), quality of life 25.0 (0-75) to 50.0 (19-94)]. The pain level decreased significantly in both groups. No significant difference was found between both groups regarding the subscales of FAAM, FAOS and the NRS 1 year postoperatively. CONCLUSION: Improvements in subjective ankle function, daily life activities and sports activities were observed within the first year following M-BMS. Our results suggest that preexisting and treated ankle instability did not compromise subjective outcome in patients treated with M-BMS in the first postoperative year. LEVEL OF EVIDENCE: Level IV.

Overweight patients benefit from high tibial osteotomy to the same extent as patients with normal weights but show inferior mid-term results.

PURPOSE: The purpose of this prospective study was to analyze the impact of obesity on the clinical and radiological outcomes 6 years after open-wedge high tibial osteotomy (HTO). METHODS: A total of 120 prospectively recorded patients with medial compartment osteoarthritis underwent open-wedge HTO between 2008 and 2011. The study cohort was frequently examined over a minimum of a 6-year follow-up. The cohort was divided into three groups according to body mass index (BMI): normal weight patients (BMI < 25 kg/m2), pre-obese patients (BMI 25-30 kg/m2) and obese patients (BMI > 30 kg/m2). Clinical and functional outcomes (Oxford Knee Score, Hospital for Special Surgery Score, Lequesne Score, Tegner Activity Scale), subjective health-related quality of life (SF-36), change in mechanical limb alignment (mTFA) as well as conversion to unicompartmental or total knee arthroplasty (TKA) were evaluated. To compare clinical scoring between the groups, univariate variance analysis was applied. Changes in outcome variables over time were analyzed with dependent t tests. RESULTS: From 120 patients, 85 were followed-up over a 6.7-year period on average (6-11.8 years) after HTO. The mean BMI was 28.6 ± 4.6 kg/m2. Each group showed a significant pre- to postoperative increase in all recorded scores (p < 0.05). In absolute terms, both mental and clinical scores of overweight patients did not reach the peak values of the normal weighted population during the period of observation. There was a conversion to TKA in 10.5% after an average of 50.1 ± 25.0 months following surgery. A total of five complications occurred without significant differences (BMI < 25: n = 1, BMI 25-30: n = 2, BMI > 30: n = 2; n.s.). There was a mean pre- to postoperative (six weeks after surgery) correction difference of 6.9° ± 3.2° (mTFA) with higher loss of correction over time in overweight patients. CONCLUSION: In terms of clinical outcome and health-related quality of life, overweight patients may receive a benefit from open-wedge HTO to the same extent as patients with normal weights and show similar complication rates. However, they have inferior preoperative clinical and functional results and mid-term results after open-wedge HTO compared to patients with normal weights. LEVEL OF EVIDENCE: Level III.

Influence of axial limb rotation on radiographic lower limb alignment: a systematic review.

INTRODUCTION: The influence of limb malrotation on long-leg radiographs (LLR) is frequently discussed in literature. This systematic review aimed to describe the influence of limb rotation on alignment measurements alone and in combination with knee flexion, and determine its clinical impact. MATERIALS AND METHODS: A literature search was conducted in June 2021 using the databases MEDLINE, Cochrane, Web of Science (Clarivate Analytics), and Embase. The search term ((radiograph OR X-ray) AND (position OR rotation) AND limb alignment) was used. Database query, record screening, and study inclusion and exclusion were performed by two reviewers independently. Experimental studies (using either specimens or synthetic bones) or clinical studies (prospective or retrospective using radiographs of patients) analyzing the influence of limb rotation on anatomic and mechanical limb alignment measurements were included. Characteristics and results of the included studies were summarized, simplified, and grouped for comparison to answer the research question. Studies were compared descriptively, and no meta-analysis was performed. RESULTS: A total of 22 studies were included showing large heterogeneity, comprising studies with cadavers, patients, and synthetic bones. Most studies (7 out of 8) reported that external rotation (ER) causes less apparent valgus and leads to more varus and internal rotation (IR) causes more valgus and leads to less varus. However, there is no consensus on the extent of rotation influencing alignment measures. Studies reported about an average change of > 2° (n = 4) and < 2° (n = 4) hip-knee-ankle angle (HKA) between 15°IR and 15°ER. There is a consensus that the impact of rotation on mechanical alignment is higher if additional sagittal knee angulation, such as knee flexion, is present. All five studies analyzing the influence of rotation combined with knee flexion (5°-15°) showed an HKA change of > 2° between 15°IR and 15°ER. CONCLUSION: Malrotation is frequently present on LLR, possibly influencing the measured alignment especially in knees with extension deficit. Surgeons must consider this when measuring and treating deformities (high tibial osteotomy or total knee arthroplasties), and analyzing surgical outcomes. Especially in patients with osteoarthritis with knee extension deficits or postoperative swelling, the effect of malrotation is significantly greater.

Increased tibial tubercle-trochlear groove and patellar height indicate a higher risk of recurrent patellar dislocation following medial reefing.

PURPOSE: Identifying anatomical risk factors on recurrent dislocation after medial reefing is important for deciding surgical treatment. The present study aimed to retrospectively analyze the preoperative magnetic resonance imaging (MRI)-based parameters of patients treated with medial reefing and whether these parameters lead to a higher risk of recurrent dislocation. METHODS: Fifty-five patients (18.6 ± 6.6 years) who underwent medial reefing after primary traumatic patellar dislocation (84% with medial patellofemoral ligament [MPFL] rupture) were included. Patients were followed up for at least 24 months postoperatively (3.8 ± 1.2 years) to assess the incidence of recurrent patellar dislocation. In patients without recurrent dislocation, the Kujala and subjective IKDC scores were assessed. Moreover, the tibial tubercle-trochlear groove (TT-TG), sulcus angle, patellar tilt, patellar shift, and lateral trochlea index (LTI) were measured. The patellar height was measured using the Caton-Dechamps (CDI), Blackburne-Peel (BPI), and Insall-Salvati index (ISI). The cohort was subclassified into two groups with and without recurrent dislocation. Differences between groups were analyzed with respect to the MRI parameters. RESULTS: Forty percent had a pathological sulcus angle of > 145°, 7.2% had an LTI of < 11°, 47.3% had a patellar tilt of > 20°, and 36.4% had a TT-TG of ≥ 16 mm. Increased patellar height was observed in 34.5, 65.5, and 34.5% of the patients as per CDI, BPI, and ISI, respectively. Nineteen (34.5%) patients suffered from recurrent dislocation. Compared with patients without recurrent dislocation, those with recurrent dislocation had a significantly lower LTI (p = 0.0467). All other parameters were not significantly different between the groups. Risk factor analysis showed higher odds ratios (OR > 2), although not statistically significant, for MPFL rupture (OR 2.05 [95% confidence interval 0.38-11.03], LTI (6.6 [0.6-68.1]), TT-TG (2.9 [0.9-9.2]), and patellar height according to ISI (2.3 [0.7-7.5]) and CDI (2.3 [0.7-7.5])). Patients without recurrent dislocation had a Kujala score of 93.7 ± 12.1 (42-100) points and an IKDC score of 90.6 ± 11.7 (55.2-100) points. CONCLUSION: Anatomical, MRI-based parameters should be considered before indicating medial reefing. A ruptured MPFL, an LTI < 11°, a TT-TG ≥ 16 mm, a patellar tilt > 20 mm, and an increased patellar height according to ISI and CDI were found to be associated, although not significantly, with a higher risk (OR > 2) of recurrent patellar dislocation after medial reefing. Thorough preoperative analysis is crucial to reduce the risk of recurrent dislocation in young patient cohorts. LEVEL OF EVIDENCE: Level IV.

Rotation osteotomy of the distal femur influences coronal femoral alignment and the ischiofemoral space.

INTRODUCTION: Despite the fact that osteotomies around the knee represent well-established treatment options for the redistribution of loads and forces within and around the knee joint, unforeseen effects of these osteotomies on the remaining planes and adjacent joints are still to be defined. It was, therefore, the aim of this study to determine the influence of a distal femoral rotation osteotomy on the coronal limb alignment and on the ischiofemoral space of the hip joint. MATERIALS AND METHODS: Long-leg standing radiographs and CT-based torsional measurements of 27 patients undergoing supracondylar rotational osteotomies of the femur between 2012 and 2019 were obtained and utilized for the purpose of this study. Postoperative radiographs were obtained after union at the osteotomy site. The hip-knee-ankle angle (HKA), the mechanical lateral distal femur angle (mLDFA), and the ischiofemoral space were measured. Comparison between means was performed using the Wilcoxon-Mann-Whitney test. RESULTS: Twenty-seven patients underwent isolated supracondylar external rotation osteotomy to reduce the overall antetorsion of the femur. The osteotomy resulted in a 2.4° ± 1.4° mean increase in HKA and 2.4 mm ± 1.7 mm increase in the ischiofemoral space (p < 0.001). CONCLUSION: Supracondylar external rotation osteotomy of the femur leads to valgisation of the coronal limb alignment and increases the ischiofemoral space. This is resultant to the reorientation of the femoral antecurvature and the femoral neck. When planning a rotational osteotomy of the lower limb, this should be appreciated and may also aid in the decision regarding osteotomy site.

Distance from the magnification device contributes to differences in lower leg length measured in patients with TSF correction.

INTRODUCTION: In absence of deformity or injury of the contralateral leg, the contralateral leg length is used to plan limb lengthening. Length variability on long-leg weight-bearing radiographs (LLR) can lead to inaccurate deformity correction. The aim of the study was to (1) examine the variability of the measured limb length on LLR and (2) to examine the influence of the position of the magnification device. MATERIALS AND METHODS: The limb lengths of 38 patients during deformity correction with a taylor-spatial-frame were measured retrospectively on 7.3 ± 2.6 (4-13) LLR per patient. The measured length of the untreated limb between LLR were used to determine length variability between LLR in each patient. To answer the secondary aim, we took LLR from a 90 cm validation distance. A magnification device was placed in different positions: at the middle of the 90 cm distance (z-position), 5 cm anterior and 5 cm posterior from the z-position, at the bottom and top of the validation distance as well as 5 cm medial and 15 cm lateral from the z-position. RESULTS: The measured length variability ranged within a patient from 10 to 50 mm. 76% of patients had a measured limb length difference of ≥ 2 cm between taken LLR. Compared to length measurement of the 90 cm test object with the magnification device in the z-position (90.1 cm), positioning the device 5 cm anterior led to smaller (88.6 cm) and 5 cm posterior led to larger measurements (91.7 cm). The measured length with the magnification device at the bottom, top, medial or lateral (90.4; 89.9; 90.2; 89.8 cm) to the object differed not relevantly. CONCLUSIONS: High variability of limb length between different LLR within one patient was observed. This can result from different positions of the magnification device in the sagittal plane. These small changes in positioning the device should be avoided to achieve accurate deformity correction and bone lengthening. This should be considered for all length and size measurements on radiographs.

Cortical bone thickness of the distal radius predicts the local bone mineral density.

AIMS: The distal radius is a major site of osteoporotic bone loss resulting in a high risk of fragility fracture. This study evaluated the capability of a cortical index (CI) at the distal radius to predict the local bone mineral density (BMD). METHODS: A total of 54 human cadaver forearms (ten singles, 22 pairs) (19 to 90 years) were systematically assessed by clinical radiograph (XR), dual-energy X-ray absorptiometry (DXA), CT, as well as high-resolution peripheral quantitative CT (HR-pQCT). Cortical bone thickness (CBT) of the distal radius was measured on XR and CT scans, and two cortical indices mean average (CBTavg) and gauge (CBTg) were determined. These cortical indices were compared to the BMD of the distal radius determined by DXA (areal BMD (aBMD)) and HR-pQCT (volumetric BMD (vBMD)). Pearson correlation coefficient (r) and intraclass correlation coefficient (ICC) were used to compare the results and degree of reliability. RESULTS: The CBT could accurately be determined on XRs and highly correlated to those determined on CT scans (r = 0.87 to 0.93). The CBTavg index of the XRs significantly correlated with the BMD measured by DXA (r = 0.78) and HR-pQCT (r = 0.63), as did the CBTg index with the DXA (r = 0.55) and HR-pQCT (r = 0.64) (all p < 0.001). A high correlation of the BMD and CBT was observed between paired specimens (r = 0.79 to 0.96). The intra- and inter-rater reliability was excellent (ICC 0.79 to 0.92). CONCLUSION: The cortical index (CBTavg) at the distal radius shows a close correlation to the local BMD. It thus can serve as an initial screening tool to estimate the local bone quality if quantitative BMD measurements are unavailable, and enhance decision-making in acute settings on fracture management or further osteoporosis screening. Cite this article: Bone Joint Res 2021;10(12):820-829.

Supracondylar rotation osteotomy of the femur influences the coronal alignment of the ankle.

PURPOSE: Osteotomies represent well-established treatment-options for the redistribution of loads and forces within and around the knee-joint. Effects of these osteotomies on the remaining planes and adjacent joints are not fully understood. The aim of this study was to determine the influence of a distal-femoral-rotation-osteotomy on the coronal alignment of the ankle. It was hypothesized that supracondylar-external-rotation-osteotomy of the distal femur leads to a change in the coronal orientation of the ankle joint. METHODS: Long-leg standing radiographs and CT-based torsional measurements of 27 patients undergoing supracondylar-rotational-osteotomy of the femur between 2012 and 2019 were obtained and utilized for the purpose of this study. Postoperative radiographs were obtained after union at the osteotomy-site. The hip-knee-ankle-angle (HKA), the mechanical-lateral-distal-femur-angle (mLDFA), and Tibia-Plafond-Horizontal-Orientation-Angle (TPHA) around the ankle were measured. Comparison between means was performed using the Wilcoxon-Mann-Whitney test. RESULTS: Twenty-seven patients with high femoral antetorsion (31.3° ± 4.0°) underwent supracondylar-external-rotation-osteotomy. The osteotomy led to a reduced antetorsion (17.4 ± 5.1; p < 0.001) and to a valgisation of the overall limb-alignment. The HKA decreased by 2.4° ± 1.4° (p < 0.001). The TPHA decreased by 2.6° (p < 0.001). CONCLUSIONS: Supracondylar external rotation osteotomy of the femur leads to lateralization of the weight bearing line at the knee and ankle due to valgisation of the coronal limb alignment. The mobile subtalar joint has to compensate (inversion) for the resulting valgus orientation of the ankle to ensure contact between the foot and the floor. When planning a rotational osteotomy of the lower limb, this should be appreciated - especially in patients with a preexisting valgus alignment of the lower extremities or restricted mobility in the subtalar joint.