Biomechanical effects of cranial closing wedge osteotomy on joint stability in normal canine stifles: an ex vivo study.

BACKGROUND: Cranial closing wedge osteotomy (CCWO) is a functional stabilisation technique for cranial cruciate ligament (CrCL) ruptures. This biomechanical study aimed to evaluate the influence of CCWO on the stability of the stifle joint. Eighteen Beagle stifle joints were divided into two groups: control and CCWO. The stifle joints were analyzed using a six-degree-of-freedom robotic joint biomechanical testing system. The joints were subjected to 30 N in the craniocaudal (CrCd) drawer and proximal compression tests and 1 Nm in the internal-external (IE) rotation test. Each test was performed with an extension position, 135°, and 120° of joint angle. RESULTS: The stifle joints were tested while the CrCLs were intact and then transected. In the drawer test, the CCWO procedure, CrCL transection, and stifle joint flexion increased CrCd displacement. The CCWO procedure and CrCL transection showed an interaction effect. In the compression test, the CCWO procedure decreased and CrCL transection and stifle joint flexion increased displacement. In the IE rotation test, CCWO, CrCL transection, and stifle joint flexion increased the range of motion. CONCLUSIONS: CCWO was expected to provide stability against compressive force but does not contribute to stability in the drawer or rotational tests. In the CCWO-treated stifle joint, instability during the drawer test worsened with CrCL transection. In other words, performing the CCWO procedure when the CrCL function is present is desirable for stabilizing the stifle joint.

Tibial tuberosity-trochlear groove distance is significantly decreased by medial closing wedge distal femoral osteotomy.

PURPOSE: While medial closing wedge distal femoral osteotomy (MCWDFO) has been used to address patella instability combined with valgus malalignment, its impact on patellofemoral parameters remains uncharted. Hence, this study seeks to establish a three-dimensional (3D) planning of MCWDFO and measure its effect on the tibial tubercle - trochlear groove distance (TTTG) through simulation and calculation. METHODS: MCWDFO with a stepwise increment of one-degree varisation (1°-15°) was performed on 3D surface models of 14 lower extremities with valgus malalignment and 24 lower extremities with neutral alignment of the lower limb, resulting in a total of 608 simulations. Anatomic landmarks were employed to measure hip-knee-ankle angle (HKA), TTTG, and femoral torsion for each simulation. A mathematical formula was adopted to calculate TTTG changes following MCWDFO, and subsequently the mean simulated and calculated TTTG values were compared. Following a standardised protocol, MCWDFO was performed without rotational changes. RESULTS: MCWDFO exhibited an almost linear reduction in TTTG, at a rate of approximately -1.05 ± 0.13 mm per 1° of varisation, demonstrating a strong negative correlation (R = -0.83; p < 0.001). Limb alignment did not exert an influence on TTTG change; however, it correlated with tibial plateau width. The mean difference between the simulated and calculated TTTG values amounted to 0.03 ± 0.03 mm per 1° varisation (p < 0.001). CONCLUSION: The TTTG distance is linearly reduced by 1.05 mm for every 1° of varisation within the varus correction range of 0°-15° during MCWDFO. Patients with combined valgus and patellar instability may benefit from MCWDFO due to frequently pathological TTTG. LEVEL OF EVIDENCE: Level III, descriptive laboratory study.

Economic evaluation of high tibial osteotomy: Closing wedge is more cost-effective than open wedge technique when analysing the KOOS-12 improvement.

PURPOSE: The purpose of this study was to compare the cost-effectiveness of two techniques for performing a knee valgus osteotomy: opening wedge high tibial osteotomy (OW-HTO) vs closing wedge high tibial osteotomy (CW-HTO). METHODS: In this economic evaluation study, a cost-effectiveness analysis from the perspective of the Spanish public healthcare system was performed, comparing OW-HTO with CW-HTO. All patients with medial knee osteoarthritis who underwent one of these procedures between 2018 and 2020 in our institution were included. The cost analysis included operating room, implant, graft and hospital admission costs. Functional outcomes (KOOS-12, Tegner activity scale, pain and satisfaction) and radiological outcomes (hip-knee-ankle angle, medial proximal tibial angle, tibial slope and patellar height) were analysed. The cost-effectiveness ratio was obtained by calculating the cost of improving the minimal clinically important difference (MCID) of KOOS-12 for each procedure. All costs are expressed in 2020 euros. RESULTS: Fifty-one patients met the inclusion criteria (27 OW-HTO and 24 CW-HTO). Good to excellent functional outcomes, significant pain reduction (>6 points) and high patient satisfaction (>9/10) were observed in both groups. Both techniques yielded excellent radiological outcomes. N.s. differences in functional or radiological outcomes improvements between both procedures were found. However, the OW-HTO group presented a higher total cost than the CW-HTO group (4612.1 ± 765.6€ vs. 1827.1 ± 701.9€; p < 0.001). The cost-effectiveness ratio was 818.1 ± 46.8 €/MCID for the CW-HTO procedure and 2414.3 ± 115.2 €/MCID for the OW-HTO procedure (p = 0.025). CONCLUSION: The CW-HTO procedure presented a cost-effectiveness ratio almost three times lower than the OW-HTO procedure. Both techniques allowed to achieve of good to excellent functional outcomes, significant pain reduction and high patient satisfaction while correcting the varus limb malalignment and the metaphyseal tibial varus in patients with medial compartment osteoarthritis. LEVEL OF EVIDENCE: Level III; economic study.

Soft Tissue Structures at Risk With a Percutaneous Focal Dome Osteotomy: A Cadaver Study.

The focal dome osteotomy allows deformity correction through frontal plane rotation, and if needed, anterior or posterior translation. This percutaneous technique allows extracapsular ankle realignment with minimal soft tissue dissection. While circumventing a standard anterior incision, this technique encounters soft tissue structures that must be considered. Focal dome osteotomies were simulated on 10 fresh-frozen below the knee cadavers. Centered proximal to the tibial plafond at the physeal scar, a radial arm using a 4-hole Rancho cube was used to map the dome. Medial, lateral, and central incisions were made to allow access for drilling and measured to nearby anatomic structures. Among 10 cadavers, the age and weight were 70 ± 7.96 years and 134.7 ± 30.8 pounds, respectively. In all cadavers, the hole below the most proximal posthole provided the ideal position for the creation of the osteotomy. The medial and central incisions were closest to the tibialis anterior tendon measuring 3.37 ± 2.48 mm and 0.43 ± 0.9 mm, respectively. The lateral incision and half-pin used to create the distal axis of rotation were closest to the extensor hallucis longus tendon, measuring 1.97 ± 1.92 mm and 1.27 ± 1.5 mm, respectively. Drilling the second hole from the top on a 4-hole Rancho cube, forming a 2.50 cm radial arm, created the ideal osteotomy arc. Though neurovascular structures were further away from respective incision and half-pin sites compared to tendons, in several specimens, anatomic variations held them closer, warranting preoperative handheld Doppler and mapping. Care should be taken to protect anterior ankle anatomy during dissection, drilling, and completing the osteotomy.

Biomechanical consequences of Zadek osteotomy in insertional achilles tendinopathy: A virtual surgical simulation study.

BACKGROUND: The Zadek osteotomy modified by Taylor (ZO) is a surgical technique used to treat insertional Achilles tendinopathy (IAT) by reducing the heel's prominence and elevating the Achilles tendon insertion. This study aims to analyze the biomechanical consequences of IAT after ZO using a virtual surgical simulation with a specific software. METHODS: A retrospective analysis of 20 wtbearing computed tomography (WBCT) scans of IAT patients was conducted. Using Disior's BonelogicTM software, 3D models were created from WBCT images. Virtual ZO was performed on these models, and various biomechanical parameters were measured before and after the virtual osteotomy. RESULTS: The virtual ZO showed significant statistical differences in the average of the calcaneal length (p < 0.001), Fowler Philips angle (p < 0.001), calcaneal pitch (p < 0.001), and the sagittal talocalcaneal angle (p < 0.001). CONCLUSIONS: The virtual ZO analysis suggests that this procedure can decrease the Fowler Philips angle, shorten the calcaneus, modifying specifically the sagittal alignment. LEVEL OF EVIDENCE: IV; case series.

Effect of sequential burr passes on osteotomy magnitude and calcaneal morphology in minimally invasive Zadek osteotomy.

PURPOSE: This study aimed to evaluate the impact of each burr pass on degree of correction, gap size and calcaneal morphology in MIS Zadek osteotomy. METHODS: MIS Zadek osteotomy was performed on ten cadaveric specimens using a 3.1 mm Shannon burr. After each burr pass, the osteotomy gap was manually closed, and the subsequent burr passes were carried out with the foot held in dorsiflexion, which was repeated five times. Lateral X-rays were taken before and after each burr pass. Two independent reviewers measured the dorsal calcaneal length after each burr passage, as well as changes in several calcaneal parameters including X/Y ratio, Fowler Philip angle, and Böhler angle. RESULTS: The average decrease in dorsal calcaneal cortical length with each burr pass was as follows: 2.6 ± 0.9 mm at the 1st pass, 2.4 ± 1 mm at the 2nd pass, 2 ± 1 mm at the 3rd pass, 1.6 ± 1 mm at the 4th pass, and 1.4 ± 0.7 mm at the 5th pass. The Fowler Philip and Böhler angles consistently decreased while the X/Y ratio consistently increased following each consecutive burr pass. Interobserver reliability analysis demonstrated good agreement for all parameters. CONCLUSION: The results revealed the trends of length and anatomical changes in the calcaneus with each burr pass. On average, a dorsal wedge resection of 10 mm was achieved after 5 burr passes. This data can aid surgeons in determining the optimal number of burr passes required for a particular amount of resection, ensuring the attainment of the desired patient-specific surgical outcome.

Satisfactory long-term outcomes for combined anterior cruciate ligament reconstruction and lateral closing wedge high tibial osteotomy.

PURPOSE: A combined anterior cruciate ligament (ACL) reconstruction and high tibial osteotomy (HTO) is considered a valuable treatment in young patients affected by symptomatic medial osteoarthritis and ACL deficiency. However, only a few studies have investigated the outcomes of this procedure, especially in the long term. Therefore, the aim of this study is to report clinical and radiographic outcomes of ACL reconstruction and lateral closing wedge HTO at a mean of 14 years of follow-up. METHODS: Patients were prospectively evaluated pre-operatively, after 6.5 ± 2.7 years and 14.3 ± 2.2 years. Patient-reported outcome measures (PROMs) were collected, knee laxity was assessed through KT-1000 arthrometer, and limb alignment and knee osteoarthritis were evaluated on long-cassette radiographs. Survivorship of the surgical procedure was calculated through the Kaplan-Meier method. RESULTS: 32 patients were initially enrolled and completed the mid-term evaluation (6.5 ± 2.7 years), and 23 patients (72%) were available for the final evaluation at 14.3 ± 2.2 years after surgery. Statistically significant improvement was found for all the clinical scores (VAS, WOMAC, Tegner, subjective IKDC, objective IKDC) between the pre-operative status and the mid-term follow-up (p < .001). VAS, subjective IKDC and objective IKDC showed no statistically significant differences (p > .05) between the mid-term and the final follow-up; a significant decrease of WOMAC (p < .05) and Tegner (p < .001) was found from mid-term to final follow-up. Significant progression of osteoarthritis was found for all the knee compartments. The survivorship was 95.7% at 5 years, 82.6% at 10 years, and 72.8% at 15 years. CONCLUSIONS: Combined ACL reconstruction and lateral closing wedge HTO showed satisfactory clinical outcomes and survivorship at a mean of 14 years follow-up. LEVEL OF EVIDENCE: IV.

Opening- and closing-wedge high tibial osteotomy are comparable and early full weight bearing is safe with angular stable plate fixation: a meta-analysis.

PURPOSE: The purpose of this study was to establish the gold standard for surgical technique, fixation, and rehabilitation for HTO in patients with unicompartmental knee osteoarthritis. METHODS: Medline, Embase, and SPORTDiscus databases were searched up to April 2022. Included were (1) randomized controlled trials (RCTs) comparing opening-wedge HTO (owHTO) and closing-wedge HTO (cwHTO), (2) biomechanical studies and prospective patient studies comparing biomechanical and clinical results for plate fixators, and (3) RCTs comparing an early versus delayed full-weight-bearing (FWB) protocol. RESULTS: The pooled results for the surgical technique showed no significant differences between owHTO and cwHTO for most PROMs on pain, activity, and risk for conversion to TKA. The cwHTO group showed a slightly better improvement in KOOS/WOMAC pain scores (4.51; 95% CI 1.18-7.85), and a significantly lower change in posterior tibial slope (p = 0.03). The pooled results for the fixation method showed the highest force at maximum failure for the Activmotion (Newclip Technics, France), Aescula (B. Braun Korea, Korea), 2nd generation Puddu (Arthrex Inc., USA), and TomoFix plate (Depuy Synthes, Switzerland). The pooled results for the rehabilitation protocol showed no significant differences between the early full-weight-bearing (FWB) group and the delayed FWB group for functional scores, complication rates, and delayed unions. CONCLUSION: Both owHTO and cwHTO reduced pain and improved knee function. Locking plate fixation should be used for owHTO. An early FWB protocol has proven to be safe in patients with small corrections, no hinge fractures, and non-smokers. LEVEL OF EVIDENCE: Level II.

Less risk of conversion to total knee arthroplasty without significant clinical and survivorship difference for opening-wedge high tibial osteotomies in varus knee deformities at 10-year minimum follow-up compared to closing-wedge high tibial osteotomies.

PURPOSE: The purpose of this study was to evaluate the clinical outcomes and survivorship at minimum 10-year follow-up of patients undergoing primary valgisation high tibial osteotomy (HTO) for medial osteoarthritis (OA), treated by Opening-Wedge HTO (OW-HTO) or Closing-Wedge HTO (CW-HTO). METHODS: This was a retrospective cohort study of consecutive patients presenting to a single institution undergoing HTO for isolated medial compartment OA. Two hundred and twenty three HTOs for isolated medial tibio-femoral OA were performed between January 2002 and December 2010. Patients were eligible if they had minimum 10-year follow-up and received either a CW or OW-HTO. Fifteen (6.7%) patients died and twenty-five (11.2%) were lost to follow-up. One hundred and eighty three (82.1%) patients were included in the final analysis and divided into two groups: OW-HTO (96/183; 52.4%) and CW-HTO (87/183; 47.6%). Range of motion, KSS, KOOS scores, and conversion to TKA rate were analyzed between groups. Both groups were comparable regarding age, arthrosis stage, gender, ASA score and BMI at the time of HTO. Survival analysis was conducted with re-intervention for TKA as the end point. RESULTS: At the time of HTO, mean age was 55 years ± 7.9 (27-73.9) with 72.7% of patients being male. The mean follow-up was 13.3 years ± 2.7 (10-19). Sixty-four (34.9%) patients underwent TKA at a mean delay of 9.3 years ± 3 (3-16). The conversion to TKA rate was significantly higher in the CW-HTO group versus the OW-HTO group: 42.5% (37/87) versus 28.1% (27/96) (p = 0.04). The survival at 15-year follow-up was 59.2% in the OW-HTO group versus 54.6% in the CW-HTO group (n.s.). At 13-year follow-up, KSS Function score was significantly better in the OW-HTO (90.9 versus 82.4; p = 0.007). No significant difference was observed between the two groups regarding the KOOS score, KSS Knee Score and complication rate. CONCLUSION: At mean follow-up of 13 years, no significant clinical and survivorship difference was observed between the two groups. The conversion to TKA was significantly lower following OW-HTO. Minor correction was associated with risk of requiring subsequent TKA. LEVEL OF EVIDENCE: Retrospective case series, IV.

Favorable rates of return to activity and work following lateral closing wedge distal femoral osteotomy for femoral-based symptomatic varus malalignment: an analysis at a mean 6-year follow-up.

PURPOSE: To evaluate return to sport (RTS), work (RTW) and clinical outcomes following lateral closing wedge distal femoral osteotomy (LCW-DFO) for symptomatic femoral varus malalignment. METHODS: Consecutive patients who underwent LCW-DFO for symptomatic varus malalignment between 12/2007 and 03/2018 were included. The International Knee Documentation Committee (IKDC) Score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Lysholm score, Tegner Activity Scale, and visual analogue scale (VAS) for pain were collected preoperatively and at a minimum of 24 months postoperatively. RTS and RTW were assessed by questionnaire. RESULTS: Thirty-two patients (mean age: 45.9 ± 12.3 years), who underwent LCW-DFO for femoral-based varus malalignment (6.4 ± 3.0°), were included at a mean follow-up of 72.7 ± 39.1 months. The patient collective significantly improved in IKDC (51.8 ± 12.3 to 61.8 ± 21.5, p = 0.010; 95% CI = 3-21), WOMAC (26.7 ± 17.6 to 12.5 ± 13.5; p < 0.001; 95% CI = 21-6) and Lysholm (46.5 ± 19.4 to 67.9 ± 22.8 points (p < 0.01; 95% CI = 9-31)) scores at final follow-up. The VAS for pain reduced significantly postoperatively (4.8 ± 2.3 points to 2.6 ± 2.3 points (p = 0.002; 95% CI = 0-3)). Following LCW-DFO, 96% of patients returned to sports at a mean of 5.3 ± 2.9 months. Yet, a shift to lower impact sports compared to one year preoperatively was observed, with patients participating in a significantly lower number of high-impact disciplines (p = 0.024) and fewer hours in high-impact sports (p = 0.034). Twenty-three out of 24 patients returned to work at a mean 11.4 ± 10.9 weeks, with 18 patients reporting a similar or superior working ability. CONCLUSION: Undergoing isolated LCW-DFO for symptomatic femoral-based varus malalignment enabled the vast majority of patients to RTS and RTW along with a significant functional improvement at mid-term follow-up. However, patients' expectations have to be adequately managed regarding a limited probability to return to high-impact sports and work after surgery. LEVEL OF EVIDENCE: Retrospective case series; Level IV.

Joint line obliquity after lateral closing-wedge high tibial osteotomy does not adversely affect clinical and radiological outcome: a 5-year follow-up study.

PURPOSE: To analyze the association between change in knee joint line obliquity (KJLO) and patient-reported outcome, radiological progression of osteoarthritis, and surgical survival after lateral closing-wedge high tibial osteotomy (HTO). METHODS: A cohort of 180 patients treated in one single hospital with lateral closing-wedge HTO was examined. KJLO was defined by the medial proximal tibial angle (MPTA). To assess the association between KJLO and patient-reported outcome, radiological progression of osteoarthritis, and surgical survival, patient groups were defined: I, postoperative MPTA < 95.0°; II, postoperative MPTA ≥ 95.0°; A, MPTA change < 8.0°; B, MPTA change ≥ 8.0°. Propensity score matching was used for between-groups (I and II, A and B) covariates matching, including age, gender, preoperative lower limb alignment, preoperative medial joint space width (mJSW), preoperative Western Ontario and McMaster Universities osteoarthritis Index (WOMAC) score, wedge size, and postoperative follow-up time. Patient-reported outcome was assessed by the WOMAC questionnaire, radiological progression of osteoarthritis by mJSW and Kellgren-Lawrence (KL) grade progression (≥ 1) preoperatively and at follow-ups (> 2 years). Failure was defined as revision HTO or conversion to knee arthroplasty. RESULTS: After propensity score matching, groups I and II contained 58 pairs of patients and groups A and B contained 50 pairs. There were no significant differences in postoperative WOMAC score or surgical failure rate between groups I and II or between groups A and B (p > 0.05). However, the postoperative mJSW was significantly lower in group I than group II (3.2 ± 1.6 mm vs 3.9 ± 1.8 mm; p = 0.018) and in group A than group B (3.0 ± 1.7 mm vs 3.7 ± 1.5 mm; p = 0.040). KL grade progression rate was significantly higher in group I than group II (53.4% vs 29.3%; p = 0.008) and in group A than group B (56.0% vs 28.0%; p = 0.005). CONCLUSION: Increased KJLO (postoperative MPTA ≥ 95.0°) or MPTA change ≥ 8.0° after lateral closing-wedge HTO does not adversely affect patient-reported outcome, radiological progression of osteoarthritis, or surgical survival at an average 5-year follow-up. LEVEL OF EVIDENCE: III, retrospective cohort study.

In slope-changing osteotomy one millimeter is not one degree: results of an artificial intelligence-automated software analysis.

BACKGROUND: Anterior closing wedge osteotomies (ACWO) are performed in revision anterior cruciate ligament (ACL) surgery to correct an excessive posterior tibial slope (PTS). PURPOSE: With the help of automated planning software, this study investigates the assumption that 1mm of wedge height gives 1° of slope correction (1:1). METHODS: Fifty patients underwent ACWO, with the wedge height calculated using the 1:1 formula. Pre- and postosteotomy PTS were measured manually, and the achieved post-operative PTS was compared with the target PTS of 5.3° ± 1.9. The X-ray analysis was repeated virtually with the automated software, which also recommended a resection height. These parameters were then compared with the manually obtained parameters. RESULTS: Using a 1:1 formula, wedge heights of 8.5mm ± 2.3 was resected to achieve a PTS of 4.2° ± 0.32. This showed an overcorrection of 1.6° ± 0.8 from the target slope. This was consistent with the data from the automated software, which recommended a lower wedge height of 7.7mm ± 2.9. CONCLUSION: In trans-tubercle ACW, using a wedge height (mm) to slope correction (°) ratio of 1:1 can lead to slight over-correction. Automated software planning is useful for planning correction osteotomies in the sagittal plane.

Influence of lateral hinge fractures on biplanar medial closing-wedge distal femoral osteotomy for valgus knee: a new classification of lateral hinge fracture.

BACKGROUND: The purpose of this study was to examine the influence of lateral hinge fractures in medial closing-wedge distal femoral osteotomy (MCWDFO) on bone union. METHODS: Twenty-one patients were followed-up for more than 1 year after MCWDFO. The incidence and type of hinge fracture, as well as the course of bone healing, were investigated. Slow healing was defined as bone union was not obtained until 3 months after surgery. RESULTS: Hinge fractures were observed in 12 cases (57%). There were three types of hinge fractures. Type 1: the lateral cortex was completely cut through (4 cases), type 2: the osteotomy line was too proximal (6 cases), and type 3: the hinge point was significantly medial (2 cases). There was a significant difference in the mean correction angles between hinge fracture and no-fracture cases, with the mean angles being 13.8 ± 4.0° and 9.6 ± 3.1°, respectively. Sixty-seven percent (8/12) of cases with hinge fractures developed slow healing. Among the hinge fracture cases, when there was no displacement of the hinge fracture and good contact with the anterior flange, 40% (2/5) of cases developed slow healing. If there was displacement of the hinge or no contact of the anterior flange, 86% (6/7) of cases developed slow healing. In contrast, only 11% (1/9) of subjects who did not have a hinge fracture, developed slow healing. In 67% (6/9) of cases with slow healing, a correction loss of 2° or greater (average: 4.3 degrees valgus) was observed. There were no cases of non-union. Clinical outcomes at 1 year showed no significant difference between the groups with and without hinge fractures. CONCLUSIONS: There is a very high risk of hinge fracture in patients undergoing MCWDFO. Hinge fractures often lead to slow healing and a loss of correction. We recommend the endpoint of the distal lateral cortex of the femur as the ideal hinge point for the prevention of hinge fractures. Bone union is obtained slowly in even all hinge fracture cases without revision surgery. Consequently, surgical results are not affected by the occurrence of hinge fracture at 1 year.

Radiographic Evaluation of Isolated Continuous Compression Staples for Akin Osteotomy Fixation.

Continuous compression implants (nitinol staples) are gaining popularity secondary to their lower profile, less demanding technique, and less surgical dissection. Biomechanical support exists; however, clinical data is limited in the foot/ankle. This study's purpose is to determine the efficacy of nitinol staples to achieve stable, bony healing in Akin osteotomies and examine their clinical outcomes, complications, re-operations, and pain scores. We performed a retrospective chart review on 90 patients (93 osteotomies) who underwent an Akin osteotomy using a nitinol staple over a 2-year period. Radiographs were randomized and independently reviewed by 3 blinded foot and ankle surgeons. Osteotomies were deemed healed if greater than 50% of the osteotomy contained bridging bone, partially healed as less than 50% bridging bone, and nonunion as no healing, broken hardware, or loss of reduction. Visual analog scale pain scores were analyzed. Radiographic union was seen in 98.9% of Akin osteotomies (92/93), with no loss of reduction or broken staples (0/95). Only 3.2% (3/93) of patients returned to the operating room unplanned: 1 infection (1.1%), 1 symptomatic hardware removal (1.1%), and 1 traumatic disruption of fixation (1.1%). Postoperative pain scores were significantly lower than preoperative. Staples are lower profile and technically less demanding compared to headed screws, plates, and tension band constructs. They offer continuous compression of the osteotomy and are rigid enough to maintain reduction. Based on the findings of this paper, the use of staples provides robust and stable fixation for Akin osteotomies and has low complication and high healing rates.

The Akin osteotomy without fixation in open hallux abducto-valgo correction surgery - A single center retrospective analysis of 286 cases.

BACKGROUND: Description of a large cohort of Akin osteotomies without fixation (286 feet), to depict the mean angular correction, to analyze complication rates and to pull over with rates described in the literature with other techniques. METHODS: Retrospective single-center cohort study. Five radiologic measurements analyzed preoperatively and postoperatively until fusion was completed. Evaluation of all peri- and postoperative complication rates. Evaluation of correlation between complications and the presence of diabetes mellitus (DM), smoking and rheumatic disease. RESULTS: Between 2011 and 2018, 222 patients, 286 feet (147 left, 139 right) met the inclusion criteria. We found an average difference between pre-op and post-op at 3 months of distal articular set angle (DASA) of 7.0 degrees and average interphalangeal joint obliquity angle (IPOA) of 12.0 degrees (p < 0.001). All cases achieved fusion but in 5.9 % (17/289 cases) of cases, we observed delayed consolidation. The average union time in these cases was 22.1 weeks. Hyperextension of the distal fragment (mal union in plantar flexion) was observed in 7 cases (2.4 %). None of the 7 cases required correction. Out of 286 surgeries, 8 (2.7 %) required reoperation, but only one case for a hypocorrection required Akin's re osteotomy. Regarding the inter- and intra-observer correlations, good and excellent reliability are observed for all parameters under consideration. CONCLUSION: The absence of internal fixation would appear not to impair osteotomy healing and complication rates compared with techniques with fixation would not appear to be worse. The results are encouraging; nevertheless, we believe that further studies need to be performed in order to confirm the data. LEVEL OF EVIDENCE: IV retrospective cases series.

Metatarsal head restoration versus dorsal closing-wedge osteotomy in the treatment of advanced-stage Freiberg's disease.

PURPOSE: Freiberg's disease is mostly characterized by osteonecrosis of second metatarsal head and is widely seen in adolescent women. Metatarsal head restoration technique is a novel surgical procedure intended to protect intact articular surface and regenerate avascular bone under cartilage. This study aimed to evaluate and compare the results and clinical outcomes of metatarsal head restoration technique with those of dorsal closing-wedge osteotomy technique in patients with advanced-stage Freiberg's disease. METHODS: In this retrospective study, 60 patients who were operated for Freiberg's disease were evaluated. Patients were divided into two groups as who underwent metatarsal head restoration and dorsal closing-wedge osteotomy. Groups were compared according to "American Orthopaedic Foot & Ankle Society score" (AOFAS), "visual analog score" (VAS) and passive "range of motion" (ROM) score. RESULTS: Thirty-two feet of 29 patients underwent metatarsal head restoration, while 33 feet of 31 patients were subject to dorsal closing-wedge osteotomy. Mean AOFAS score increased from 58.72 ± 6.89 to 89.35 ± 7.43 following metatarsal head restoration, while it increased from 54.13 ± 6.12 to 78.24 ± 6.54 after dorsal closing-wedge osteotomy. Mean VAS score decreased from 6.89 ± 1.18 to 1.33 ± 0.64 after metatarsal head restoration, while it decreased from 6.64 ± 0.92 to 2.71 ± 1.91 following dorsal closing-wedge osteotomy. Mean ROM increased from 12.25° ± 1.65 to 56.28° ± 2.77 after metatarsal head restoration, and it increased from 11.18° ± 0.66 to 47.65° ± 2.05 after dorsal closing-wedge osteotomy (all p < 0.05). In addition, postoperative mean AOFAS (p = 0.044), VAS (p = 0.041) and passive ROM (p = 0.034) scores improvement were found to be statistically significantly better in the metatarsal head restoration group. CONCLUSION: This study revealed that metatarsal head restoration is a safe and successful surgical technique. It leads to better results than dorsal closing-wedge osteotomy in patients with stages 3-4 Freiberg's disease. LEVEL OF EVIDENCE: III.

Dislocated hinge fractures are associated with malunion after lateral closing wedge distal femoral osteotomy.

PURPOSE: To evaluate the incidence, morphology, and associated complications of medial cortical hinge fractures after lateral closing wedge distal femoral osteotomy (LCW-DFO) for varus malalignment and to identify constitutional and technical factors predisposing for hinge fracture and consecutive complications. METHODS: Seventy-nine consecutive patients with a mean age of 47 ± 12 years who underwent LCW-DFO for symptomatic varus malalignment at the authors' institution between 01/2007 and 03/2018 with a minimum of 2-year postoperative time interval were enrolled in this retrospective observational study. Demographic and surgical data were collected. Measurements evaluating the osteotomy cut (length, wedge height, hinge angle) and the location of the hinge (craniocaudal and mediolateral orientation, relation to the adductor tubercle) were conducted on postoperative anterior-posterior knee radiographs and the incidence and morphology of medial cortical hinge fractures was assessed. A risk factor analysis of constitutional and technical factors predisposing for the incidence of a medial cortical hinge fracture and consecutive complications was conducted. RESULTS: The incidence of medial cortical hinge fractures was 48%. The most frequent morphological type was an extension fracture type (68%), followed by a proximal (21%) and distal fracture type (11%). An increased length of the osteotomy in mm (53.1 ± 10.9 vs. 57.7 ± 9.6; p = 0.049), an increased height of the excised wedge in mm (6.5 ± 1.9 vs. 7.9 ± 3; p = 0.040) as well as a hinge location in the medial sector of an established sector grid (p = 0.049) were shown to significantly predispose for the incidence of a medial cortical hinge fracture. The incidence of malunion after hinge fracture (14%) was significantly increased after mediolateral dislocation of the medial cortical bone > 2 mm (p < 0.05). CONCLUSION: Medial cortical hinge fractures after LCW-DFO are a common finding. An increased risk of sustaining a hinge fracture has to be expected with increasing osteotomy wedge height and a hinge position close to the medial cortex. Furthermore, dislocation of a medial hinge fracture > 2 mm was associated with malunion and should, therefore, be avoided. LEVEL OF EVIDENCE: Prognostic study; Level IV.

Consistent indications, targets and techniques for double-level osteotomy of the knee: a systematic review.

PURPOSE: To systematically review and critically appraise the literature on double-level osteotomy (DLO) of the knee, and determine the indications, contraindications, targets and outcomes. MATERIALS AND METHODS: A systematic literature search was performed on PubMed, Embase®, and Cochrane for studies that reported on DLO by any technique or approach, including indications, contraindications, and targets for DLO, as well as patient-reported outcome measures (pROMS) and radiographic angles. RESULTS: Twelve eligible studies were found: 9 case series and 3 studies that compared DLO to high-tibial osteotomy (HTO). In all studies, DLO was performed by medial opening-wedge tibial osteotomy and lateral closing-wedge femoral osteotomy. Seven specified that DLO was performed if simple HTO would exceed thresholds of postoperative medial proximal tibial angle (MPTA), lateral distal femoral angle (LDFA), and/or predicted wedge size. The targets were 88°-95° for MPTA, 84°-89° for LDFA, and 0°-4° for hip-knee-ankle (HKA) angle. The 3 comparative studies reported lower MPTA after DLO (89.6°-92.5°) than after HTO (91.5°-98.3°). All 3 reported similar postoperative HKA after DLO (0.2°-4.4°) as HTO (0.4°-4.8°); only 2 compared postoperative LDFA, which was lower after DLO (85.4° and 84.9°) than HTO (88.7° and 88.8°). Two comparative studies reported postoperative overall KOOS which was slightly lower after DLO (351-403) than HTO (368-410); only 1 study reported separate items of the KOOS. CONCLUSION: There was relative consistency between studies on the indications, targets and techniques for DLO. Furthermore, while the comparative studies reported similar preoperative MPTA, LDFA and HKA, the postoperative MPTA and LDFA were lower after DLO than after HTO, though both treatments achieved equivalent postoperative HKA. LEVEL OF EVIDENCE: IV, systematic review.

Comparative evaluation of pinning and cast fixation vs. external fixation after lateral closing-wedge osteotomy for cubitus varus in children.

BACKGROUND: Cubitus varus has been regarded as a poor functional and cosmetic consequence of supracondylar humerus fracture in children. The aim of this study was to assess the clinical and radiologic outcomes of cubitus varus treatments based on fixation methods: Kirschner (K)-wire and cast fixation or external fixation. METHODS: Forty consecutive patients with cubitus varus secondary to supracondylar fractures were retrospectively enrolled between October 2015 and December 2018. Following lateral closing-wedge osteotomy, those undergoing K-wire and cast fixation were included in group A (n = 21) and those who were treated with external fixation comprised group B (n = 19). We measured the bony union, elbow joint range of motion, and carrying angle. The clinical and radiographic results were assessed according to the Bellemore criteria. RESULTS: No significant difference was found between the 2 groups in terms of age, gender, operation duration, union time, and postoperative elbow range of motion (P > .05). A significant difference was noted, however, in postoperative carrying angle and results according to Bellemore criteria in group B (P < .05). No nonunion, myositis ossificans, or neurovascular injury was found at follow-up in the 2 groups. In group A, revision surgery was needed for residual varus in 1 patient and lateral condylar prominence was found in 2 patients. In group B, a superficial pin-site infection occurred in 2 patients, who were treated successfully with oral antibiotics. CONCLUSIONS: Both K-wire and external fixation after lateral closing-wedge osteotomy are reliable and effective for the treatment of cubitus varus in children. Compared with the K-wire method, external fixation achieves better functional and cosmetic results with a shorter learning curve.

Analysis of bone union after medial closing wedge distal femoral osteotomy using a new radiographic scoring system.

INTRODUCTION: To compare bone union after medial closing wedge distal femoral osteotomy (MCWDFO) with that after lateral closing wedge distal femoral osteotomy (LCWDFO) using a novel scoring system. MATERIALS AND METHODS: The data of 30 patients who received biplanar MCWDFO for valgus knees (MCWDFO group) were retrospectively examined and compared to that of 22 patients (25 knees) who underwent biplanar LCWDFO via a double-level osteotomy (DLO) for varus knees (LCWDFO group). The progression of bone union of the transverse osteotomy plane in the femur was assessed using a newly developed scoring system using radiographs taken immediately after surgery and 3 and 6 months postoperatively. The scoring system is based on a scale of zero to six points with higher scores indicating better bone union. The incidence of hinge fractures was assessed using CT images, and the rates of reoperation were evaluated using medical record data. RESULTS: The mean bone union score was significantly lower in the MCWDFO group than in the LCWDFO group 3 months (2.1 ± 1.9 vs. 3.7 ± 1.7, P < 0.01) and 6 months (3.8 ± 2.1 vs 4.9 ± 1.5, P < 0.05) postoperatively. The incidence ratio of hinge fractures was significantly higher in the MCWDFO group than in the LCWDFO group (70.0% vs. 32.0%, P < 0.01). Two patients in the MCWDFO group underwent reoperation for delayed bone union or non-union. CONCLUSION: Bone union progression was slower and hinge fractures were more frequently observed after MCWDFO than after LCWDFO via DLO. MCWDFO is technically challenging, and patients must be monitored closely during and after surgery.