Abstract
Debate remains regarding whether knee realignment osteotomy should be performed concomitantly with additional major knee reconstruction procedures or if it should be performed in a staged fashion. The purpose of this study is to analyze complications that occur when distal femoral osteotomy or high tibial osteotomy is performed concomitantly with other significant reconstructive procedures. Thirty-five patients with a minimum of one year follow up were identified. These patients underwent either high tibial or distal femoral osteotomy with concomitant significant additional knee reconstruction which included cartilage resurfacing requiring an arthrotomy, ligament reconstruction, meniscal transplantation, or extensor mechanism realignment requiring tibial tubercle osteotomy. Overall, 13/35 (37%) of these patients suffered at least one major or minor complication. Major complications occurred in 20.0% (7/35) and minor complications occurred in 25.7% (9/35). In conclusion, the rate of complication for combined osteotomy and reconstructive knee surgery is similar to that seen in cases of osteotomy done alone and combined surgery is advocated.
INTRODUCTION
High tibial osteotomy (HTO) and distal femoral osteotomy (DFO) are widely accepted treatment options for younger and more active patients with symptomatic medial or lateral compartment gonarthrosis associated with varus or valgus alignment.1-14 Realignment osteotomy procedures are also recommended when lower extremity malalignment is present in patients undergoing reconstructive procedures for ligament laxity, meniscus deficiency, chondral defects or patellar instability.1,4,6-8,12,14,15 Failure to address varus or valgus malalignment may result in premature failure of the associated knee reconstructive procedures to correct these conditions.
The timing of realignment osteotomy and additional reconstructive procedures of the knee is an area of debate.1,4,6-8,14 Concurrent osteotomy and reconstruction decreases total recovery time, eliminates a second surgery, and facilitates early rehabilitation and return of these patients to activities of daily living and sports.1,4,6-8,10,12,14,15 On the other hand, both realignment osteotomies and knee reconstruction procedures have associated post-operative complications and some authors have recommended staging procedures to avoid increased complications.7,8 Major complications from HTO and DFO include extension loss, arthrofibrosis, valgus or varus overcorrection, nonunion, neurovascu-lar injury.2,4,7,11 These problems may be magnified with large corrections, with prolonged operative time, and in non-compliant patients. Additional knee reconstructive procedures may also increase this complication rate by prolonging the operative time and making the rehabilitative process more difficult.
The purpose of this retrospective study was to examine the complications that occurred in patients who underwent knee realignment osteotomy with additional reconstructive procedures of the knee in a single setting.
MATERIAL AND METHODS
After IRB approval, a retrospective review was performed to identify all high tibial osteotomy (HTO) and distal femoral osteotomy (DFO) procedures performed by the senior author from January 2001 to January 2006. Chart review was performed to document demographic data, knee surgeries performed prior and subsequent to the osteotomy, additional procedures done in combination with the osteotomy, and minor and major complications after surgery. Concomitant procedures that were deemed significant included: cartilage resurfacing using an arthrotomy (autologous cartilage implantation and osteochondral allograft transplant), ligament reconstruction, meniscal transplantation, and extensor mechanism realignment requiring tibial tubercle osteotomy.
Complications that were considered minor included hardware pain, superficial infection, anterior knee pain, hematoma, delayed union, and tendonitis. Complications that were considered major included hardware failure, motion loss requiring intervention, intra-articular fracture, deep venous thrombosis, deep infection, exostosis, neuroma, non-union, and failure of alignment correction.
HTO patients and DFO patients were grouped together and analyzed. Patients were also separated by additional procedure performed with the knee osteotomy for statistical analysis. Complication rates were analyzed for the entire cohort and stratified by group. A group of patients that underwent HTO and DFO without an additional reconstructive procedure during the same time period was also identified. The complications incurred by this group were also recorded for comparison.
Radiographic Measurements
All patients had pre-operative two-legged standing full length radiographs. A post-operative radiograph was taken at four and eight weeks after surgery and then as required until bone consolidation at the osteotomy site was evident. Post-operative films were also analyzed for timing of bony union. Delayed union was defined as lack of bridging callous and presence of radiolucent areas within the opening wedge defect past a period of three months postoperatively.13
Operative Techniques and Rehabilitation
Osteotomy is routinely performed concurrently with other significant knee procedures by the senior author. The only exception occurs when a patient requires three or more significant interventions, such as ACL reconstruction, osteotomy and meniscal transplant. In these situations, a portion of the reconstruction is staged. One patient during this study period was selectively staged for this reason and not included in this analysis.
When indicated, arthroscopy for chondroplasty, meniscectomy, microfracture or loose body removal was performed prior to osteotomy. Opening wedge osteotomies were performed in all HTO cases. For HTO cases, an opening wedge osteotomy was performed using a medial proximal tibial approach. Osteotomies were fixed with the Arthrex HTO plate (Arthrex, Inc.; Naples, FL). Both opening and closing wedge techniques where used with DFO. Lateral distal femoral opening wedge osteotomy was performed with fixation using the Arthrex DFO plating system (Arthrex, Inc,; Naples, FL). Medial distal femur closing wedge osteotomy was fixed with a 90 degree fixed angle blade plate (Synthes, Inc; West Chester, PA). Allograft fresh frozen femoral head was fashioned into wedges and morselized for bone grafting the opening wedge osteotomies.
Knees with associated patellofemoral mal-alignment were treated with tubercle realignment as described by Fulkerson16 after HTO or DFO was performed. Osteotomy combined with meniscus transplantation was performed as previously described.1 For combined ACL reconstruction and osteotomy cases, arthroscopy was performed first for preparation of the notch. Realignment osteotomy was then performed and fixed, followed by drilling of the tibial and femoral tunnels and graft placement and fixation. In knees with posterolateral instability, posterolateral reconstruction was performed subsequent to the realignment osteotomy.
General anesthesia and tourniquet application were routinely applied in all cases. Prophylactic antibiotics and prophylaxis against deep-vein thrombosis were used in all cases. Canister drainage was used in some cases if there was a concern for bleeding. Immediately after surgery, isometric quadriceps and active ankle exercises were instituted. Knee range of motion exercises, patellar mobilization, straight-leg raises, and electrical muscle stimulation began on the first postoperative day, with home exercises supervised by a physical therapist. For the first week, local ice, mild compression, and elevation were used to minimize edema. The patients were instructed to remain at home, except for physical therapy visits, to maximize limb elevation and lessen lower extremity edema. Patients were restricted to non-weight bearing on their leg up to the eighth week postoperatively depending on signs of radiographic osteotomy healing.
Statistical Analysis
Descriptive statistics were calculated for all variables. Chi-square tests and Fisher's Exact tests were used to test for differences in proportion. Statistical significance was set at P ≤ 0.05. All statistics were calculated using SAS v. 9.1 (SAS Institute, Inc.; Cary, NC).
RESULTS
From January 2001 to January 2006, knee realignment osteotomy was performed concurrently with additional reconstructive knee procedures in 35 patients. The patients were followed up at a minimum of twelve months with a mean follow-up of 45 months (range, 12-80 months). The mean age of the cohort was 28.7 years (Range 15-50 years). There were 25 males and 10 females (Table 1).
TABLE 1.
Characteristics of knee osteotomy patients undergoing isolated osteotomy and osteotomy combined with a significant additional procedure
| Combined Procedure N=35 | Isolated Procedure N=43 | |
|---|---|---|
| Age (mean ± std) | 28.7 ± 11.0 | 39.0 ± 10.7 |
| Gender | ||
| Male | 25 (71.4%) | 28 (65.1%) |
| Female | 10 (28.6%) | 15 (34.9%) |
| Osteotomy Procedure | ||
| HTO | 23 (67.5%) | 35 (81.4%) |
| DFO | 12 (34.3%) | 8 (18.6%) |
| Patients with Prior | ||
| Ipsilateral Knee Surgery | 29 (82.9%) | 35 (81.4%) |
Additional procedures consisted of 14 allograft osteo-chondral transplant procedures, 3 autologous chondro-cyte implantation procedures, 7 meniscus transplants, 6 tibial tubercle transfer/advancements, 5 ACL reconstructions, and 1 posterolateral reconstruction. Of these 35 patients, 23 patients underwent HTO and 12 patients underwent DFO.
In total, 13 of 35 (37.1%) patients experienced at least one minor or major complication. Major complications occurred in 20.0% (7/35) and minor complications occurred in 25.7% (9/35). 11/23 HTO patients suffered a complication and 2/12 DFO patients suffered a complication. This result was found to be statistically significant (p<0.05). Table 2 presents the details of the minor and major complications that occurred. Two patients suffered joint contracture and this was the most frequent major complication. Six of the 13 minor complications were related to hardware pain.
TABLE 2.
Frequencies of complications occurring with isolated osteotomy and osteotomy combined with additional procedures
| Combined Procedure N=35 | Isolated Procedure N=43 | |
|---|---|---|
| Major Complications | ||
| Intra-articular fracture | 1 | 1 |
| Compartment syndrome | 0 | 1 |
| Deep infection | 0 | 1 |
| Exo stasis | 1 | 1 |
| Hardware failure | 1 | 3 |
| Correction failure | 1 | 1 |
| Contracture | 2 | 2 |
| Neuroma | 1 | 0 |
| Total | 7 | 10 |
| Minor Complications | ||
| Superficial infection | 2 | 6 |
| Hardware pain | 6 | 3 |
| Delayed union | 0 | 3 |
| Hematoma | 0 | 4 |
| Anterior knee pain | 4 | 10 |
| Pes anserinus pain | 1 | 1 |
| Total | 13 | 27 |
Hardware failure occurred in 1 patient who underwent HTO with tibial tubercle realignment osteotomy. The distal screw was found to be broken 140 days after surgery. The HTO site was re-operated and chronic inflammation and metallosis without infectious symptoms was found. Re-fixation was achieved and the osteotomy went on to heal without difficulty.
A loss of correction found during the follow-up period was observed in 1 patient who underwent DFO with an OAT procedure. This case was re-operated and corrected without residual deformity. Intra-articular fracture of the lateral tibial plateau was seen intra-operatively in 1 patient during opening of the osteotomy. The correction was not affected and additional fixation was placed. Two patients had loss of range of motion requiring manipulation under anesthesia. Neuroma and exostosis were each seen in one patient and both were re-operated. Nonunion and DVT were not seen in any cases. Doppler studies where only performed in patients who had a clinical suspicion for DVT.
Twenty-nine of 35 patients had undergone a prior surgery to the affected knee. A total of 57 prior procedures had been performed on this group, 15 of which were considered major procedures. The breakdown of prior surgery is presented in Table 3. Table 4 presents the procedures that occurred subsequent to the combined osteotomy and knee reconstruction. Nine patients underwent hardware removal, 8 patients underwent arthroscopy and 3 patients had a manipulation under anesthesia.
TABLE 3.
Procedures performed on the ipsilateral knee prior to knee osteotomy
| Procedures Preformed Previous to Knee Osteotomy | Combined Procedure N=35 |
|---|---|
| Major Procedures | |
| Prior Knee Osteotomy | 3 |
| Ligament Reconstruction | 5 |
| Cartilage Resurfacing | 2 |
| Fulkerson Osteotomy | 1 |
| Hardware Removal | 3 |
| Fracture Repair | 1 |
| Epiphyseal Repair | 0 |
| Resection of Proximal Tibial Fibula Articulation | 0 |
| Total | 15 |
| Minor Procedures | |
| Arthroscopy (Debridement or Diagnostic) | 19 |
| Meniscectomy/Meniscus Repair | 13 |
| Marrow Stimulation | 8 |
| Lateral Release | 2 |
| Total | 42 |
TABLE 4.
Procedures performed on the ipsilateral knee after realignment osteotomy
| Procedures Preformed Subsequent to Knee Osteotomy | Combined Procedure N=35 |
|---|---|
| Major Procedures | |
| Hardware Removal | 9 |
| Ligament Reconstruction | 0 |
| Autologous Chondrocyte Implantation | 1 |
| Exostectomy | 1 |
| I&D | 0 |
| Fulkerson Osteotomy | 2 |
| Bursectomy | 1 |
| Fasciotomy | 0 |
| Total Knee Arthroplasty | 1 |
| Manipulation Under Anesthesia | 3 |
| Total | 18 |
| Minor Procedures | |
| Arthroscopy (Debridement or Diagnostic) | 8 |
| Total | 8 |
One patient in our cohort underwent subsequent autologous chondrocyte implantation after lateral opening wedge DFO with osteochondral allograft transplant. After the initial procedures the patient presented 16 months later with increased pain and crepitus after re-injuring the knee. At that time the patient underwent autologous chondrocyte implantation and Fulkerson tibial tubercle transfer.
During the study period there was one patient who underwent ligament reconstruction subsequent to knee osteotomy. This patient presented with varus knee deformity, complete ACL disruption, and posterolat-eral instability after suffering a non-contact pivot type injury. Opening wedge HTO osteotomy was performed initially. Knee instability persisted and five months later the patient underwent arthroscopic ACL reconstruction and posterolateral corner reconstruction. This patient was not included in the analysis because the case was selectively staged as more than 2 additional procedures were required.
During this same time period 43 patients underwent an isolated HTO or DFO without concomitant major surgery. This included 35 HTO and 18 DFO patients. The average age of this group was 39.0 years and there were 28 males and 15 females. This group of patients was significantly older than the combined group (p<0.05) (Table 1). For comparison, this group suffered 10 major complications and 27 minor complications (Table 2). Major complications were experienced by 7/43 patients and minor complications were suffered by 14/43 patients. These rates of complications were not significantly different from the rates of complications for those patients undergoing concomitant reconstructive procedures. 13/43 patients in this group underwent subsequent surgery. This was significantly lower than the group undergoing concomitant additional reconstructive surgery (p<0.05). There were 3 cases of hardware failure in patients who underwent isolated HTO. These failures occurred at 104, 144, and 368 days after surgery.
DISCUSSION
Debate exists regarding whether realignment osteotomy around the knee should be done simultaneously with other major knee reconstructive procedures or in a staged fashion. The primary concern with combined surgeries is the possibility of increased risk for complications related to the surgery. Combined surgery results in longer operative times and often includes more extensive exposures and incisions around the knee. However, combined reconstructive surgeries decrease overall recovery times and eliminate a second anesthetic and surgery.
In the current study, major complications were found in 20.0% (7/35) of patients that underwent an additional procedure with a knee osteotomy. Minor complications were found in 25.7% (9/35) of patients in this cohort. The study group consisted of both DFO and HTO procedures done in conjunction with cartilage resurfacing, ligament reconstruction or patellar realignment. Limited information exists regarding combining osteotomy with other reconstructions. The literature available primarily relates to performing ACL reconstruction with HTO. In a series of 27 patients who underwent HTO and ACL reconstruction Boss et al.4 reported sensory disturbances in 2 patients and 5 patients that required arthroscopies and manipulation for limited motion. Dejour et al.6 reported on 44 combined HTO and ACL cases with 3 major complications and 16 minor complications. The authors in both of these studies favored the simultaneous approach based on the results of these studies.
In contrast, in a study looking at a population of younger patients with varus malalignment and anterior cruciate ligament deficiency, Noyes et al.8 recommended correction of varus alignment with HTO first before considering ACL reconstruction. Based on a series of 27 patients Lattermann et al.7 advised that patients under 40 years old with medial OA and chronic anterior instability should undergo HTO first and then a staged ACL reconstruction can be performed if instability persists. In their series 8 patients that underwent combined ACL and HTO surgery suffered a total of 6 major complications. Two of these complications were subsequent ACL rupture. In this same study 11 patients underwent HTO alone and 8 patients underwent HTO followed by a staged ACL reconstruction. In these groups 4 of 11 and 3 of 8 suffered major complications.
Osteotomy around the knee alone carries an established risk of complication, regardless of technique. Lattermann et al. reported a major complication rate of 33% (10/30) in a cohort of HTO patients.7 Complications reported in this study included extension defects, marked valgus overcorrection, intra-articular fracture, severe pain over the buttress plate, DVT, and peroneal nerve injury. Dejour et al. reported a minor complication rate of 36.4% (16/44) in a group of patients who underwent HTO.6 Minor complications reported included asymptomatic calf thromboses, hematoma and superficial wound infection. At our institution, during the studied time frame, a cohort of 43 patients underwent isolated HTO or DFO by the senior surgeon. In this group major complications occurred in 16.3% (7/43) of patients and minor complications occurred in 32.6% (14/43) of patients.
The most common major complication in our combined reconstruction cohort was contracture seen in 2 patients (2/35, 6%). There was one hardware failure in a patient that underwent tubercle transfer in conjunction with the HTO. Spahn reported implant failure in 16.6% of isolated HTO cases using the Puddu plate.11 One intra-articular fracture was observed in each of our groups which is relatively low in comparison to other reports in the literature.2,8,10,11,15 Spahn reported that intra-articular fracture occurred in 14.6% of patients.11 This complication seems to be more common in cases with correction angles more than 12.5°. To prevent this complication, the enlargement of the osteotomy must be performed carefully. In addition, we advocate that the osteotomy be made below the guide pins placed for osteotomy alignment, as opposed to above the guide pins. This helps to prevent intra-articular fracture from occurring. Previous series have reported infection rates after HTO of 2.3-54.5%.11 Spahn reported infection in 4/85 patients undergoing medial opening wedge HTO.11 In the current study, deep infection did not occur in patients who underwent a combined procedure and in 1 patient who underwent an isolated knee osteotomy (1/43, 2%). This patient was treated by debridement and parenteral antibiotic therapy. Superficial infections occurred in 2 patients (2/35, 6%). There were no cases of nonunion or delayed union in our series. Warden et al. reported that non-union occurred in 1.6% cases, delayed union in 6.6%.13
Risks also exist for other reconstructive procedures that are often combined with osteotomy. The rate of major complication following ACL reconstruction is relatively small with rates of septic arthritis under 1%,17 a rate of venous thrombosis of less than 1%,18 and rates of subsequent surgery for debridement, manipulation or other reason of 14.7%.19 The risk of rupture of the ACL is approximately 3%.19>,20 Minimal information exists regarding complications following cartilage resurfacing procedures requiring an arthrotomy although serious adverse events and subsequent surgical procedures have occurred in up to 54% patients.21
This study is inherently limited due to its retrospective design. In addition, our cohort undergoing osteotomy and other simultaneous reconstruction is a heterogeneous group that includes both HTO and DFO patients, in addition to several different reconstructions. However, we felt that the data of the group as a whole would provide more information than looking at several very small cohorts of patients undergoing the exact same procedure. It is also difficult to compare our results to studies examining patients only undergoing osteotomy since our cohort was quite young with a mean age of 28.7 years. By contrast, during this same time frame, the average age of patients undergoing isolated osteotomy was 39 years. In addition, since none of the osteotomy patients were undergoing staged procedures we were not able to directly compare overall complication rates for staged versus non-staged groups. Lastly, our study reports complications at a minimum of 12 months follow up. Longer term follow up may reveal additional information. However, it was felt that the vast majority of complications occur within this time frame.
As a conclusion, we believe that simultaneous osteotomy and knee reconstruction procedures can be valuable, and ultimately safe, if operative planning and technique is done carefully. Combining major knee reconstructive procedures adds significant complexity for which the surgeon must be prepared. In addition, patient compliance and motivation for the rehabilitation program are crucial. This study examines the complications experienced by patients who underwent knee realignment osteotomy with an additional significant procedure. This is a unique patient population because these are patients are younger and often have complex structural deficits of the knee compared to patients undergoing isolated knee realignment osteotomy. Our data suggests that combined osteotomy and knee reconstruction is safe and results in a risk for complication similar to that seen when osteotomy is done alone.
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