[Medial closed wedge osteotomy of the distal femur in biplanar technique and a specific plate fixator]. / Distale Femurosteotomie in schließender biplanarer Technik mit Stabilisierung durch spezifischen Plattenfixateur.

OBJECTIVE: Correction of distal femur deformity by closed-wedge biplanar osteotomy. INDICATIONS: Metaphyseal frontal plane deformities of the femur. CONTRAINDICATIONS: Osteoarthritis of the contralateral compartment, total loss of the contralateral meniscus, acute/chronic infection, limited range-of-motion, poor soft-tissue conditions at site of surgery. SURGICAL TECHNIQUE: Skin incision at metaphyseal area of femur. Local exposure of bone. Marking of planned osteotomies. Incomplete posterior osteotomies, complete anterior osteotomy. Wedge removal and closure. Radiological control of alignment. Fixation with specific plate fixator for the medial femur (TomoFix MDF). Submuscular plate fixation. Wound closure. POSTOPERATIVE MANAGEMENT: Elastic bandage, suction drain removal and walking with crutches on day 1. Partial weight bearing (15 kg) for the first 4 weeks; X­ray control on day 3 and 4 weeks after surgery, walking without crutches depending on healing of osteotomy. Thrombosis prophylaxis. RESULTS: From January 2005 to October 2008, 60 patients were treated. Average wedge size 7.6 mm; age 39.7 years; mean follow-up 21 months; 7 revision surgeries: 3 delayed/nonunion of the osteotomy, one superficial infection, one deep infection, one hematoma, and one fracture proximal of the internal plate fixator. Tegner activity score pre­/postoperative 2.8 (1-4)/5.6 (2-9); VAS score pre­/postoperative 6.8 (2-9)/3.1 (0-8). From 2014-2015, 107 femur osteotomies performed: 4 delayed healing, one plate breakage. Healing of all other osteotomies in 4-6 weeks. No loss of range-of-motion with the muscle-sparing surgical technique.

Supracondylar femur osteotomies around the knee: patient selection, planning, operative techniques, stability of fixation, and bone healing.

BACKGROUND: Similar to the re-appreciation of high tibial osteotomy (HTO), supracondylar distal femur varus osteotomy (SCO) for lateral compartment osteoarthritis (OA) of the knee has gained renewed interest as new knowledge has become available on the influence of malalignment on the development, progression and symptoms of OA. Furthermore, the less than optimal results of knee replacements (TKR) in younger patients have also led to renewed interest in joint-preserving treatment options. PURPOSE: Varus SCO has not had the same success or widespread use as valgus HTO. The goal in SCO is similar to HTO, to shift the load from the diseased to the healthy compartment, in order to reduce pain, improve function and delay placement of a TKR. Valgus OA however occurs much less frequently than varus OA and varus SCO is considered a technically more demanding procedure. In the past the surgical techniques for SCO were mainly dependent on difficult-to-use implants making the procedure more complex. Complication rates related to the failure of fixation up to 16% have been reported. DISUSSION: The new biplane osteotomy technique fixated with a locking compression plate is very stable; bone healing potential is optimal using this technique and takes 6-8 weeks. Full weight bearing before full bone healing is possible without loss of correction. CONCLUSION: In this article, patient selection, planning, surgical techniques, stability of fixation, and bone healing are discussed. Varus supracondylar osteotomy is a viable treatment option for a well-defined patient group suffering from valgus malalignment and lateral compartment osteoarthritis, and in addition may be considered in ligamentous imbalance and lateral patellofemoral maltracking.

[Supracondylar femur osteotomies around the knee. Patient selection, planning, operative techniques, stability of fixation, and bone healing]. / Suprakondyläre Femurosteotomien in Kniegelenknähe. Patientenauswahl, Planung, Operationstechniken, Fixationsstabilität und Knochenheilung.

BACKGROUND: Similar to the reappreciation of high tibial osteotomy (HTO), supracondylar distal femur varus osteotomy (SCO) for lateral compartment osteoarthritis (OA) of the knee has gained renewed interest as new knowledge has become available on the influence of malalignment on the development, progression and symptoms of OA. Furthermore, the less than optimal results of total knee replacement (TKR) in younger patients have also led to renewed interest in joint-preserving treatment options. PURPOSE: Varus SCO has not had the same success or widespread use as valgus HTO. The goal in SCO is similar to HTO, to shift the load from the diseased to the healthy ompartment, in order to reduce pain, improve function and delay placement of a TKR. Valgus OA however occurs much less frequently than varus OA and varus SCO is considered a technically more demanding procedure. In the past the surgical techniques for SCO were mainly dependent on difficult-to-use implants making the procedure more complex. Complication rates related to the failure of fixation up to 16 % have been reported. DISUSSION: The new biplane osteotomy technique fixated with a locking compression plate is very stable; bone healing potential is optimal using this technique and takes 6-8 weeks. Full weight bearing before full bone healing is possible without loss of correction. CONCLUSION: In this article patient selection, planning, surgical techniques, stability of fixation and bone healing for SCO are discussed. In the past the surgical techniques for SCO were mainly dependent on difficult to use implants making the procedure more complex. Complication rates related to the failure of fixation of up to 16 % have been reported.

Axial and torsional stability of supracondylar femur osteotomies: biomechanical comparison of the stability of five different plate and osteotomy configurations.

PURPOSE: Little is known regarding the biomechanical stability and stiffness of implants and techniques used in supracondylar femur osteotomies (SCO). Therefore, fixation stability and stiffness of implants to bone was investigated under simulated physiological loading conditions using a composite femur model and a 3D motion-analysis system. METHODS: Five osteotomy configurations were investigated: (1) oblique medial closing-wedge fixated with an angle-stable implant; (2) oblique and (3) perpendicular medial closing-wedge, both fixated with an angled blade plate; and lateral opening-wedge fixated with (4) a spacer plate and (5) an angle-stable lateral implant. The motion measured at the osteotomy was used to calculate the stiffness and stability of the constructs. RESULTS: The least amount of motion and highest stiffness was measured in the medial oblique closing-wedge osteotomy fixated with the angled blade plate. The lateral opening-wedge techniques were less stable and had a lower stiffness compared with the medial; the oblique saw cuts were more stable and had a higher stiffness than the perpendicular. CONCLUSION: This experimental study presents baseline data on the differences in the primary stability of bone-implant constructs used in SCO. The data in this study can be used as reference for future testing of SCO techniques. Furthermore, it is recommended that based on the differences found, the early postoperative rehabilitation protocol is tailored to the stability and stiffness of the fixation method used.

[Arthrolysis for chronic flexion deficits of the knee. An overview of indications and techniques of vastus intermedius muscle resection, transposition of the tibial tuberosity and z-plasty of the patellar tendon]. / Die Arthrolyse bei chronischen Beugedefiziten des Kniegelenks. Eine Ubersicht zu Indikation und Technik von M.-vastus-intermedius-Resektion, Tuberositaskranialisierung und Patellarsehnenverlängerung.

AIM AND METHOD: Limitations to the range of motion of the knee reduce knee function and life quality. Flexion deficits inhibit using stairs and shoe closure, and may cause social deprivation. We present a pathophysiological concept of arthrolysis of the knee for flexion deficit. Our concept divides into intra- and extra-articular factors involving knee stiffness. Extra-articular problems can be located proximally in the quadriceps mechanism and distally in the patellar tendon. RESULTS: The main proximal factor is fibrosis of the vastus intermedius muscle (MVI) which is treated by MVI-resection; the main distal factor is shortening of the patellar tendon which is treated by z-plasty of the this tendon or transposition of the tibial tuberosity. Intra-articular factors are adhesions and fat pad fibrosis. These conditions can be treated by arthroscopic or limited open arthrolysis and eventually z-plasty of the retinacula. CONCLUSION: A strict postoperative protocol is obligatory for pain control and physiotherapy. In 19 cases treated with this algorithm there was a mean flexion gain of 26 degrees. The AOSSM subjective outcome score was excellent in ten and good in seven cases after a mean follow-up of 8.2 months. This treatment protocol allows improvement in flexion, even in difficult revision cases.

Primary stability of four different implants for opening wedge high tibial osteotomy.

Since a significant number of implant failures have been reported in association with the procedure of open wedge valgus high tibial osteotomy, the initial biomechanical stability of different fixation devices was investigated in this study. Fifteen third generation Sawbones composite tibiae were used as a model. Four different plates were tested: a short spacer plate (OWO) (n = 4), a short spacer plate with multi-directional locking bolts (MSO) (n = 5), a prototype version of a long spacer plate with multi-directional locking bolts (MSOnew) (n = 2), and a long medial tibia plate fixator with locking bolts (MPF) (n = 4). All opening wedge osteotomies were performed by the same surgeon (PL) in a standardized fashion. Axial compression of the tibiae was performed using a materials testing machine under standardized alignment of the loading axis. Single load to failure tests as well as load-controlled cyclical failure tests were performed. The required force and cycles to failure were recorded. Osteotomy gap motion was measured using linear displacement transducers. Residual stability after failure of the opposite lateral cortex was analysed. Failure occurred at the lateral cortex bone-bride in all tested implants. The rigid long plate fixator (MPF) resisted the greatest amount of force (2,881 N) in the single load to failure tests. In the cyclical load-to-failure tests, the constructs with MPF resisted more than twice the amount of loading cycles when compared to the short spacer plates. The osteotomy gap motion was smallest in the MPF, with a reduction of the displacements of up to 65, 66 and 88%, when compared to OWO, MSO and MSOnew, respectively. The highest residual stability after failure of the lateral cortex was observed in MPF as well. The results suggest that the implant design strongly influences the primary stability of medial opening wedge tibial osteotomy. A rigid long plate fixator with angle-stable locking bolts yields the best results.