The efficacy of patellar decompression for improving anterior knee pain following total knee arthroplasty without patellar resurfacing

Background

Anterior knee pain remains common following total knee arthroplasty (TKA). In this study, we evaluated the efficacy of patellar decompression via drilling for the treatment of anterior knee pain following TKA without patellar resurfacing.

Methods

A prospective cohort study was performed in 271 consecutive patients who underwent primary total knee replacement with patellar decompression (study group, n = 131) or without decompression (control group, n = 140). The patients were assessed according to the Knee Society rating, clinical anterior knee pain score, and British Orthopaedic Association patient-satisfaction score in each group. Each assessment was performed without the examiner knowing whether the patella had been decompressed. Radiographic evaluations were also performed according to the Knee Society scoring system for functional activity and our own severity grade system for patellofemoral articular change.

Results

There were no adverse events following patellar decompression. The overall prevalence of anterior knee pain was not significantly different between groups (p = 0.71). However, patients presenting pain over grade II after the operation in the study group were statistically low (p = 0.01). The overall postoperative knee scores were higher in the study group, but there were no significant differences between groups (p = 0.0731). Analyses of the radiographs revealed similar postoperative outcomes in both groups of knees.

Conclusions

As we observed significantly lower rates of anterior knee pain and no patellar complications following patellar decompression via drilling in TKA without patellar resurfacing, we recommend performing patellar decompression in cases of total knee replacement without patellar resurfacing.     

Effects of local infiltration analgesia for posterior knee pain after total knee arthroplasty: comparison with sciatic nerve block

Background

Although femoral nerve block provides good analgesia after total knee arthroplasty (TKA), residual posterior knee pain may decrease patient satisfaction. We compared the efficacy of periarticular infiltration analgesia (PIA) and sciatic nerve block (SNB) for posterior knee pain.

Methods

Forty-nine patients scheduled for TKA were prospectively randomized into the PIA group (n = 25) or SNB group (n = 24) and received general anesthesia with ultrasound-guided femoral nerve block (FNB). In the PIA group, 60 ml 0.5 % ropivacaine and 0.3 mg epinephrine were injected intraoperatively into the periarticular soft tissue before inserting the components. In the SNB group, patients received ultrasound-guided SNB with 20 ml 0.375 % ropivacaine and periarticular infiltration with 20 ml normal saline and 0.3 mg epinephrine. We evaluated postoperative pain scores, posterior knee pain, frequency of rescue analgesics for 36 h, and performance time of PIA and SNB.

Results

Visual analogue pain scores at 12–24 h were significantly lower in the PIA group than in the SNB group (p < 0.05). The majority of patients had no posterior knee pain. There were no significant differences between the groups in frequency and time of first administration of rescue analgesics and in side effects. Time for performance of periarticular infiltration was significantly shorter than that for SNB (p < 0.05). The dose of intraoperative remifentanil was significantly lower in the SNB group than in the PIA group (p < 0.001).

Conclusions

The combination of FNB and PIA provides sufficient analgesia after TKA. The rapid and convenient periarticular infiltration technique could be a good alternative to SNB.     

The effect of topical scar treatment on postoperative scar pain and pruritus after total knee arthroplasty

Introduction

The surgical wound of total knee arthroplasty (TKA) needs continuous flexion and extension movement. Silicone gel treatment is widely used to treat hypertrophic scars and keloids since it is easily applied and prevents scar pain and itching. The aim of this study was to evaluate the clinical efficacy and safety of silicone gel applied to surgical scars of TKA on postoperative scar pain and pruritus.

Materials and methods

One hundred TKAs were randomized into a silicone gel group (silicone gel was applied to the wound after stitch-out for 1 month) or a placebo group. The postoperative scar pain and pruritus were evaluated with the use of a visual analog scale (VAS) at postoperative 3 months, 6 months and 1 year. Scar assessment was done using the Vancouver scar scale by evaluating scar pigmentation, vascularity, pliability, and height.

Results

Although silicone gel group showed better pigmentation and height scales than placebo group (P < 0.05), there were no significant differences in the postoperative scar pain and pruritus VAS scores between the groups (P > 0.05).

Conclusions

Application of silicone gel had no beneficial effects on scar pain and itching relief during the early postoperative period of TKA.

Level of evidence

I-Randomized Controlled Trial     

Total knee arthroplasty performed with either a mini-subvastus or a standard approach: a prospective randomized controlled study with a minimum follow-up of 2 years

Background

There is currently a trend toward minimally invasive total knee arthroplasty (TKA) to decrease the morbidity related to the standard approach. The aim of our study was to clarify whether the mini-subvastus surgical had an advantage over the standard in term of pain level, blood loss, and postoperative recovery, whether the mini-subvastus surgical was prone to radiographic malalignment, prolonged operative time, and increased complications.

Methods

In a prospective randomized study, we compared the clinical and radiological results of primary TKA using a mini-subvastus approach or a standard approach in 68 patients. The mini-subvastus approach was used on 35 patients (group I) and the standard approach on 33 patients (group II).

Results

The mean follow-up was 28 months (range 24–36 months). Patients in group I had less blood loss and better visual analogue scale score at 1 day postoperatively. They achieved active straight leg raise earlier and underwent less lateral retinacular releases. The mean Knee Society function score, Oxford knee score, and range of movement were significantly better in group I up to 9 months after surgery (all, p < 0.05). However, there were no significant differences in these parameters between the groups at final follow-up. Reduced access and visibility in group I prolonged tourniquet time by an average of 22 min and resulted in five technical errors on radiographic evaluation.

Conclusions

Patients can receive marked but temporary benefits from the mini-subvastus technique, with a definite cost: that of component malposition and prolongation of operative time.     

Design and kinematics in total knee arthroplasty

Purpose

Posterior stabilised (PS) total knee arthroplasty (TKA) design development that focused on restoring normal knee kinematics was followed by the introduction of reason-guided motion designs. Although all PS fixed-bearing knee designs were thought to have similar kinematics, reports show they have differing incidences and magnitudes of posterior femoral rollback and axial rotation. In this retrospective comparative study between two guided-motion total knee systems, we hypothesised that kinematic pattern has an influence on clinical and functional outcomes.

Methods

This study represents the continuation of a previously reported clinical and kinematics analysis. We retrospectively reviewed 347 patients treated with two different TKA designs: Scorpio NRG (Stryker Orthopedics) and Journey Bi-Cruciate Stabilised (BCS) knee system (Smith & Nephew). Two hundred and eighty-one patients were assessed clinically. Patients were divided into groups according to implanted TKA. Clinical evaluation with the Knee Injury and Osteoarthritis Outcome Score (KOOS) questionnaire was performed. Fifteen Scorpio NRG and 16 Journey BCS patients underwent video fluoroscopy during stair climbing, chair rising/sitting and step up/down at six months of follow-up.

Results

At an average 29 months of clinical follow-up, patients with Journey BCS TKAs reported better clinical results. Stiffness was more frequently reported in the Journey group (5.2 % vs 1.2 %), whereas anterior knee pain was observed in the Scorpio NRG group (1.9 %) only. Both prosthetic models reported different posterior translation of the medial and lateral contact points (CP) in all analysed motor tasks during knee flexion (BCS 10–18 mm; NRG Scorpio 2–3 mm). Both designs produced progressive external rotation of the femoral component relative to the tibia during flexion.

Conclusions

Journey BCS showed statistically significant better KOOS results. The higher posterior femoral rollback observed in the kinematic assessment of this design, associated with a better patellofemoral design, may be the reason for better clinical outcome. The reported cases of stiffness and anterolateral joint pain could be attributed to excessive medial and lateral tibiofemoral posterior translation. The NRG group demonstrated good axial rotation, but this was not coupled with physiological kinematic patterns. Patellofemoral pain can be explained by a less friendly femoral-groove design. TKA clinical–functional outcome and complications were highly influenced by the bearing geometry and kinematic pattern of prosthetic designs.     

Iatrogenic popliteus tendon injury during total knee arthroplasty results in decreased knee function two to three years postoperatively

Purpose

The popliteus tendon is known to play a key role in the stability of the posterolateral corner of the knee. While prior work suggests that isolated sectioning of the popliteus tendon has little consequence for the static stability of the knee following TKA, no studies have evaluated the effect of iatrogenic popliteal tendon injury on patient oriented outcome and knee function following TKA. The aims of this study are (1) to compare patient-oriented outcome scores of patients who suffered an iatrogenic injury to the popliteus tendon with a control group without such an injury and (2) to identify risk factors associated with iatrogenic injury to the popliteus tendon.

Methods

Fifteen patients with an iatrogenic complete transection of the popliteus tendon during TKA were compared to the 666 patients who underwent TKA during the same time period without popliteus tendon injury.

Results

Postoperatively, IKS knee scores were similar between the two groups; however, significantly lower IKS function scores were noted in the study group (71?±?31) compared to the control group (86?±?19) (p?=?0.0036). Iatrogenic popliteal tendon injury was only noted to occur in patients in whom components of size four or smaller were used.

Conclusions

Intraoperative complete section of the popliteus tendon during the performance of TKA results in decreased IKS functional scores two to three?years postoperatively. Patients with smaller knees may be at higher risk for this complication.     

Postural stability in relation to anthropometric and functional characteristics in women with knee osteoarthritis following total knee arthroplasty

Introduction

Due to the controversial information about postural stability in patients with lower limb joints osteoarthritis (OA), the following main questions are raised: how serious is the postural stability disturbance and which factors have an impact on postural stability before and after total knee arthroplasty (TKA).

Materials and methods

Force plate was used to assess postural stability and custom-made dynamometer was used to assess isometric maximal voluntary contraction (MVC) force of leg extensor muscles; besides, knee pain and knee range of motion (ROM) was evaluated in 14 female patients (aged 46–68 years) with knee OA 1 day before, and 3 and 6 months following TKA and once in healthy controls (aged 48–70). Relationship between postural stability during standing and selected anthropometric and functional characteristics were investigated with Spearman’s correlation coefficients.

Results

Remarkable reduction of knee pain and improvement in active ROM for the operated leg were shown after unilateral TKA. MVC force of leg extensor muscles achieved the preoperative level half a year after TKA. The centre of pressure (COP) of sway displacement in anterioposterior (AP) and mediolateral direction and the equivalent area of COP sway for the operated leg did not differ before, 3 and 6 months after TKA and compared to the non-operated leg. The trace speed was 6 months after TKA equal to the preoperative level. Only the COP of sway displacement in AP direction is significantly greater in knee OA patients both before and after TKA compared with healthy controls.

Conclusions

Knee OA patients’ postural stability characteristics did not differ significantly both before and after TKA. Compared to healthy controls, the COP of sway displacement in AP direction is mostly disturbed. Correlation analysis confirms that increased postural sway is associated with an increased equivalent area of COP. In knee OA patients higher body mass index ensures reduced trace speed and lower knee ROM.

Level of evidence

Prospective comparative study, Level II.     

The aetiology of total knee arthroplasty failure influences the improvement in knee function

Background

Some indications for revision total knee arthroplasty (TKA), e.g. arthrofibrosis, have been identified to yield inferior results. The aim of this study was to analyse the results of revision TKA according to aetiology of TKA failure.

Patients and methods

The results of 97 consecutive revision TKA in 97 patients stratified according to the aetiology of primary TKA failure (periprosthetic infection, aseptic loosening, instability and arthrofibrosis), were compared using the Knee Society Score (KSS). The effect of patient age, gender, BMI, American Society of Anesthesiologists (ASA) classification, interval to revision and the occurrence of complications on the outcome were also analysed.

Results

After a mean follow-up of 29 months, the KSS had significantly improved in all patient groups (p < 0.001). The analysis of variance among patient groups depicted no significant differences between preoperative KSS (p = 0.618) and postoperative KSS (p = 0.915), while the magnitude of pre- to postoperative improvement showed significant differences between the groups (p = 0.006). The aetiology of primary TKA failure had an independent influence on pre- to postoperative improvement (p = 0.014). Of the other factors analysed, only the ASA classification had an independent impact on postoperative KSS (p = 0.045).

Conclusion

The aetiology of TKA failure has an effect on the improvement in knee function from revision TKA. As no difference was observed between patient groups postoperatively, similar clinical results can be expected independent of the aetiology of primary TKA failure.     

Knee strength retention and analgesia with continuous perineural fentanyl infusion after total knee replacement: randomized controlled trial

Purpose

Despite providing adequate pain relief, a femoral nerve block can induce postoperative muscle weakness after total knee arthoplasty (TKA). Fentanyl has been shown to have peripheral effects but has not been used as a perineural infusate alone after TKA.

Methods

Sixty patients scheduled for TKA were randomized to one of three blinded groups: a continuous 24 h infusion of either fentanyl 3 μg/ml, ropivacaine 0.1 %, or 0.9 % normal saline through a femoral nerve sheath catheter at 10 ml/h. The main outcome was maximum voluntary isometric contraction (MVIC) in the quadriceps femoris (knee extension), measured by a handheld dynamometer (Nm/kg). Other variables assessed were preoperative and postoperative visual analog scale (VAS) scores, hamstrings MVIC (knee flexion), active range of motion of the operative knee, distance ambulated, incidence of knee buckling, supplemental morphine usage, postoperative side effects, and serum fentanyl levels.

Results

Quadriceps MVIC values were significantly greater in the fentanyl group compared to the group that received ropivacaine (median values, 0.08 vs. 0.03 Nm/kg; p = 0.028). The incidence of postoperative knee buckling upon ambulation was higher in the ropivacaine group compared to the fentanyl group, although not statistically significant (40 % vs. 15 %, respectively; p = 0.077). VAS scores while ambulating were not significantly different between the fentanyl group and the ropivacaine group (p = 0.270). Postoperative morphine consumption, nausea and vomiting, and resting VAS scores were similar among the three groups.

Conclusions

A continuous perineural infusion of fentanyl produced greater strength retention than ropivacaine post-TKA.     

Mediale Gonarthrosen mit Kreuzbanddefekt

Background

Low postoperative pain level, decreased length of hospital stay and accelerated rehabilitation are the major benefits of unicondylar knee arthroplasty. Especially in comparably young, not yet retired and still active patients with an isolated medial gonarthrosis, these prostheses offer many advantages. However, one important requirement to be treated with such implants is a well functioning stability system of the muscles and ligaments. Thus in patients with degenerated or destroyed anterior cruciate ligaments it is contraindicated to use this method. In order to still take advantage of this therapy for treatment of isolated arthrosis, reestablishment of the proprioceptive structures through simultaneous or staged ACL reconstruction is mandatory.

Patients and methods

Pursuing this goal we performed unicondylar knee arthroplasty with simultaneous ACL reconstruction on eligible patients. Between 2003 and 2006 we treated 32 knees with this combined surgery and followed them for a mean of 31 months (range: 10–38).

Results

The mean Knee Society Score significantly improved from 83.2 (44–103) to 167.6 (145–177) at a mean follow-up of 31 months (10–38).

Conclusions

Preliminary results of this short-term follow-up are promising. Especially the predominant number of patients who were able to return to work soon after rehabilitation and the significantly improved score postoperatively reflect the benefits of this prosthesis system in select patients. However, long-term follow-up and larger case numbers are necessary to confirm these encouraging results in the future.     

Prospective Randomized Trial Comparing Femoral Nerve Block With Intraoperative Local Anesthetic Injection of Liposomal Bupivacaine in Total Knee Arthroplasty

Background

Postoperative pain after total knee arthroplasty (TKA) may impact long-term results and incidence of complications. Femoral nerve block (FNB) provides excellent pain relief after TKA, although associated risks include weakness, delayed participation in therapy, and nerve injury. Liposomal bupivacaine (LB) is a potentially longer acting local anesthetic that may reduce postoperative pain.

Alteration of the patellar height following total knee arthroplasty

Introduction

Patellofemoral related complications after total knee arthroplasty (TKA) remain clinically relevant. The hypothesis of the present study was that the patellar height changes more than 10 % of its preoperative height after TKA. Possible influences of age, gender, side and navigation system on patellar height were evaluated separately in subgroups.

Materials and methods

A total of 107 knees were enrolled after primary TKA. The patellar height was determined for each patient preoperatively, 1 week and 1 year postoperatively on routinely performed standing lateral view radiographs at 30° knee flexion. Insall–Salvati index (ISI), modified Insall–Salvati index (MIS) as well as Miura–Kawamura index (MKI) were determined for the whole cohort.

Results

One week after TKA the ISI, MIS and MKI changed by more than 10 % in 24 (22 %), 33 (30 %) and 54 (50 %) cases, respectively. Moreover, the 1 year follow-up revealed a decrease or increase of ISI in 30 (28 %), MIS in 47 (44 %) and MK in 65 (61 %) knees. The frequency of patella alta, norma and baja preoperatively as well as 1 week and 1 year postoperatively were not significantly different. Significant differences of patellar height changes were not noted between the defined subgroups.

Conclusions

The present study demonstrates that TKA leads, at 1 week and 1 year follow-up, to patellar height alteration more than 10 % in a significant number of knee joints. However, with the use of ISI and MIS the changes of patellar height did not exceed the defined thresholds to be classified as patella alta or baja.     

Variability of gait in the early postoperative period of total knee arthroplasty with different surgical technique

Purpose

The purpose of this study was to work out an objective and sensitive method for the early postoperative period following total knee arthroplasty (TKA) in which analysis of the gait parameters is possible and also to investigate the influence of different surgical approaches for TKA on the gait during stepping in the first three months of the postoperative period.

Methods

Three groups of patients: age-matched healthy elderly patients as a control group, patients operated upon by the conventional technique and finally by the minimally invasive technique combined with computer-assisted navigation. All three groups included ten patients. The motions of knee, shoulder and pelvis were measured by ZEBRIS ultrasound-based system preoperatively plus six and 12 weeks postoperatively. From the joint motion, the variability of cadence, and the variability of knee joint motion and that of pelvis and shoulder girdle was determined.

Results

Osteoarthritis (OA) of the knee joint and TKA using both operation techniques significantly influenced the variability of stepping parameters compared to the controls. In the early postoperative period a significant difference was detected between the two groups of the operated patients in all parameters.

Conclusion

Our data prove that our method seems appropriate to provide objective measurement of the gait in the early postoperative period. The variability of motion of the patient groups approaches that of the healthy control group steadily, but does not reach them.     

Changes of body balance before and after total knee arthroplasty in patients who suffered from bilateral knee osteoarthritis

Purpose

It is still controversial whether simultaneous or staged total knee arthroplasty (TKA) is most desirable for patients with bilateral knee osteoarthritis. We retrospectively evaluated changes in balance among patients with bilateral osteoarthritis who underwent staged TKA using a gravicorder.

Methods

Patients were stratified into two groups: the unilateral group (UG) (22 patients) consisted of patients who did not undergo a second TKA within 24 months of the first TKA, and the bilateral group (BG) (20 patients) were those who had a second TKA within 12 months after initial TKA.

Results

The mean gravity center position (GCP), which indicates the translation of GCP in the mediolateral direction between pre- and post-TKA shifted to the operative side in both groups after initial surgery. While the GCP was maintained on the same side in UG over 2 years follow-up, in BG it moved to the opposite side and approached a central position after the second TKA. Locus length of GCP (LG), which indicates postural control function by proprioceptive reflex showed significant improvement after initial TKA in UG, while BG showed significant improvement after the second TKA.

Conclusions

The degree of LG improvement after initial TKA may indicate the necessity of a second TKA for patients with bilateral osteoarthritis. The current study suggests that simultaneous bilateral TKA is not always necessary for patients with bilateral knee arthritis, and that properly performed rehabilitation such as improving postural sway after initial TKA might attenuate the timing for the second TKA.     

Outcomes of long retrograde intramedullary nailing for periprosthetic supracondylar femoral fractures following total knee arthroplasty

Background

The treatment of periprosthetic supracondylar femoral fractures following total knee arthroplasty (TKA) is challenging because of osteopenia and the limited bone available for distal fixation. The purpose of this study was to report the outcomes of periprosthetic supracondylar femoral fractures treated with long retrograde intramedullary nailing.

Methods

We conducted a retrospective review of 25 patients who were treated with a long retrograde intramedullary nail for periprosthetic supracondylar femoral fractures following TKA. Clinical evaluation included range of motion of knee, Knee Society Score (KSS), Western Ontario and McMaster Universities Arthritis (WOMAC) score, and radiologic evaluation including time to union, coronal and sagittal alignment of femoral component, lower limb alignment, and implant loosening. The mean duration of follow-up after the fracture repair was 39 months (range 12–47).

Results

All 25 fractures were united with a mean time of 12 weeks (range 8–20). At the last follow-up, the mean knee flexion was 111° (range 60°–130°), the mean KSS was 81.5 (range 50–100), and the mean WOMAC score was 30.2 (range 5–55). Four (16 %) of the 25 patients developed malalignment according to Rorabeck and Taylor criteria, but all patients had a knee flexion of more than 90°. Coronal and sagittal alignments of femoral component and lower limb alignment did not differ significantly between before and after the fracture repair. Complications included the loosening or breakage of distal interlocking screws in three patients. No deep infection or prosthesis loosening was detected at the last follow-up.

Conclusions

Surgical treatment of periprosthetic supracondylar femoral fractures following TKA with long retrograde intramedullary nailing resulted in high union rates and encouraging functional outcomes.     

Neglected ununited tibial eminence fractures in the skeletally immature: arthroscopic management

Purpose

The purpose of this study was to prospectively evaluate outcomes of arthroscopic management of neglected ununited tibial eminence fractures in skeletally immature patients.

Methods

The study was conducted and cases performed by two surgeons from two centres as a prospective case series of 13 patients with neglected ununited tibial eminence fractures: nine were girls and four were boys; ten were right knees and three were left. The average age at surgery was ten [standard deviation (SD) 2.6] years. Average follow-up was 10.8 (SD 6.8) months. Primary outcome measures used for evaluation were the Objective International Knee Documentation Committee Score (IKDC), subjective IKDC and modified Lysholm knee score. Secondary outcome measures were visual analogue scales (VAS) for pain and patient satisfaction.

Results

Twelve patients had grade A objective IKDC score and one patient had grade B. Average subjective IKDC score was 80.5 (SD 16.7). Average modified Lysholm score was 91.2 (SD 8.9). Average VAS for operation satisfaction was 9.6 (SD 0.5) and for pain was 0.4 (SD 0.5). All patients showed radiological union and anatomical reduction at an average of 12.4 weeks postoperatively. At follow-up, all 13 patients showed complete range of motion (ROM). Eleven patients had negative Lachman, anterior drawer and pivot-shift tests, while two patients had grade 1 positive Lachman and negative anterior drawer and pivot-shift tests. No patient had complained of instability.

Conclusion

Neglected ununited tibial eminence fractures in skeletally immature patients achieve good functional outcome results when treated with arthroscopic reduction and internal fixation using sutures.