How precise is the identification of the center of the femoral head during total knee arthroplasty?

Background and purpose

Identification of the center of the femoral head in the coronal plane is essential during total knee arthroplasty. We evaluated a new method for localization of the center of the hip, thereby detecting the neutral mechanical axis using inter-femoral head center distances (X) measured from a radiograph. Our proposed method was compared with 3 commonly used methods using landmarks that are estimated to be 2 finger-breaths medial to the anterosuperior iliac spine (method A), 2.5 cm perpendicular to the mid-inguinal point (method I), and 1.5 cm lateral to the femoral artery (method F).

Methods

114 patients undergoing total knee arthroplasty were prospectively enrolled in the study. Four landmarks were marked and conventional anterior-posterior pelvic radiographs were taken. On the radiograph, the distance between the estimated FHC and the neutral mechanical axis was measured.

Results

The median value (mm) of the measured distance was 9 in A, 7 in I, 8.5 in F, and 5 in X. When an error of more than 3° from neutral alignment was defined as an outlier, 15% of measurements in A, 6% of measurements in I, 14% in F, and 2% in X would fall in the outlier zone.

Interpretation

The method detecting the neutral mechanical axis using inter-femoral head center distances (X) showed the least variability and the lowest percentage of outliers.Correct alignment is important for the longevity of total knee arthroplasty (TKA) (Jeffery et al. 1991, Ritter et al. 1994, Ensini et al. 2007, Sikorski 2008). Location of the center of the femoral head (FHC) intraoperatively is useful in assessment of the overall alignment of the lower limb during TKA. By estimating the mechanical axis after placement of the trial components, errors of limb alignment can be identified and corrected.Ideally, the FHC can be identified by an on-table radiograph, which, however, is time consuming and inconvenient and exposes the patient to additional radiation. Navigation systems have become more widely used to find the FHC and they may improve the accuracy of alignment, but this approach is not always available. Palpation of the anterior iliac spine (ASIS) is commonly used intraoperatively to indirectly estimate the center of the femoral head (Horton and Reckling 1995, Hooper et al. 2005). However, some authors have suggested that this is not as accurate as it is commonly presumed to be (Mullaji et al. 2010, Baldini and Adravanti 2008). Various methods using anatomical landmarks have been reported as alternatives (Horton and Reckling 1995, Matsuda et al. 2004, Sawant et al. 2004, Samarji et al. 2009). They include the use of a landmark that is located 2 finger-breaths medial to the ASIS (method A) (Hooper et al. 2005), a landmark that is located 1.5 cm lateral to the point where the femoral artery crosses the line joining the pubic tubercle and the ASIS (method F) (Sawant et al. 2004), and a landmark that is located 2.5 cm perpendicular to the midpoint of the line joining the ASIS and the symphysis pubis (method I) (Samarji et al. 2009).Here we describe a new method (X) for localization of the FHC using the inter-femoral head center distance (IFD). The IFD was measured on an anteroposterior radiograph of the pelvis preoperatively. A customized metal graduated ruler with 2 mobile pegs was used to replicate the IFD, and this ruler was fitted above the pelvic girth. Thus, these 2 pegs indicated the FHC and then we could identify the neutral mechanical axis of the lower limb.In this study, we validated the reliability of method I in identifying the neutral mechanical axis of the lower limb in vivo, and compared the precision of the methods using A and X. We also evaluated the 2 techniques using F and I. In addition, we tried to determine whether height, body mass index (BMI), and abdominal circumference had any influence on the 4 methods.     

Microsurgical reconstruction of the through-and-through defect in head and neck cancer: is it worth it?

As health resources diminish, there are compelling reasons to utilize health dollars in a fiscally responsible manner. The reconstruction of complex oromandibular defects involving mucosa, bone, and skin coverage poses one of the greatest challenges in microsurgery of the head and neck. The cancer patient who requires a through-and-through resection and microsurgical reconstruction usually has a poor prognosis. In this study, the authors examine whether this type of surgery is worthwhile in terms of cost, functional outcome, and patient satisfaction. Of 16 cases of through-and-through oromandibular reconstruction performed, the survival outcome of ten (n = 10) advanced cases requiring immediate oromandibular reconstruction (7 radial forearm flaps; 3 scapular flaps) is presented. Six cases were considered cured and required delayed reconstruction. Seven of the 10 patients died within 39 months postoperatively, while three survived up to 68 months postoperatively. The combined experience of these ten patients was examined using the Kaplan-Meier (product-limit) estimator of the survival curve. Results show that of the seven patients who died of disease, five did so within the first postoperative year. More important, among those five patients who survived for more than one postoperative year, three were still alive up to 68 months, representing a combined total of over 15 postoperative years. The probability of long-term survival is good in through-and-through oromandibular cancer patients who can survive to 1 year postoperatively, and it is proposed that microsurgical reconstruction, albeit costly, remains a worthwhile procedure,     

Arthroscopic synovectomy of the knee: Is it helpful?

We performed 211 arthroscopic synovectomies over a 10-year period. The results were assessed at follow-up of at least 2 years using the criteria of pain, synovitis, and effusion, range of motion and function. In rheumatoid knees (112 cases), we had good or excellent results in 80%. However, in seronegative arthritides (32 cases), only 60% were successful. Pigmented villonodular synovitis was successfully treated with an 11% recurrence rate (19 cases total). Synovial chondromatosis (17 cases) had no recurrences. In patients with nonspecific synovitis or posttraumatic synovitis, the synovitis was improved in 60% but only half the patients had pain relief and good function. Looking specifically at the posterior portals, there were five complications, all related to the posteromedial portal involving the saphenous nerve and vein. Overall excellent results can be achieved with due care and attention to detail.     

A broken sewing needle in the knee of a 4-year-old child: is it really inside the knee?

We report on a case of a broken needle that migrated inside the knee joint of a 4-year-old girl. Searching for any small foreign body in the knee joint is not easy in either open or arthroscopic procedures. In this case, the surgery was made more difficult because of technical delays and diagnostic difficulties in defining the surgical plane of the needle. Arthroscopic expertise and some basic precautions can minimize the morbidity to a young patient and prevent migration into the knee joint proper.     

Treatment of lateral epicondylitis: where is the evidence?

Lateral epicondylitis is the most commonly diagnosed elbow condition and affects about 1-3% of the population at large. It produces a heavy burden of workdays lost and residual impairments. Although many treatment modalities are used, few of them rest on scientific evidence and none has been proven more effective than the others. This paucity of evidence on treatments for lateral epicondylitis may stem from several sources, including the possible self-limiting nature of the condition, the lack of pathophysiological data, the methodological shortcomings of available studies, and the existence of numerous factors influencing the outcome.     

Can local corticosteroid injection in the retrocalcaneal bursa lead to rupture of the Achilles tendon and the medial head of the gastrocnemius muscle?

Purpose

The purpose of the study is to explain the cause–effect relationship in three patients who reported combined ruptures of the Achilles tendon and the gastrosoleus complex 6 months after they had received corticosteroids injections for the management of retrocalcaneal bursitis.

Methods

Three cryopreserved cadavers (three men, three left legs) were examined to assess the anatomic connection between the retrocalcaneal bursa and the Achilles tendon (distal and anterior fibers). Blue triptan medium contrast was injected.

Results

An unexpected connection between the retrocalcaneal bursa and the anterior fibers of the Achilles tendon was found in all instances.

Conclusions

Local corticosteroid injection of the retrocalcaneal bursa may help the symptoms of retrocalcanear bursitis, but pose a risk of Achilles tendon rupture. This risk–benefit has to be taken into account when corticosteroid injections are prescribed to professional and high-level athletes.     

Intrathoracic humeral head fracture-dislocation: is removal of the humeral head necessary?

Intrathoracic fracture dislocation of the humeral head due to a blunt trauma is very rare. It may be accompanied by local and systemic injuries associated with high-energy trauma. Because a limited number of cases were reported, appropriate treatment modality remains unclear. A case of intrathoracic humeral head fracture-dislocation caused by a high-speed motor vehicle accident is presented herewith, along with the treatment methods used within the scope of the current literature.     

Hip osteoarthritis: where is the pain?

BACKGROUND: Pain radiating below the knee is typically thought to originate from the lumbosacral spine rather than degenerative hip pathology. We investigated the lower limb distribution of pain using body image maps in 60 patients awaiting primary hip arthroplasty and in 60 patients awaiting spinal decompression for confirmed spinal stenosis. The perception of 33 orthopaedic registrars regarding distribution of hip pain was also assessed. RESULTS: Groin and buttock pain are significantly more common in hip osteoarthritis. The presence of groin pain is 84.3% of those sensitive for hip dysfunction with a specificity of 70.3%. Patients with hip osteoarthritis had pain below the knee in 47% of cases whereas 88.5% of orthopaedic trainees believed hip pain did not radiate below the knee. Radiographic features of osteoarthritis within the hip joint, visual analogue pain score or Oxford Hip Score have no significant association with a patient's distribution of hip pain. CONCLUSIONS: Hip pain referred below the knee is common with a degenerate hip joint and follows the distribution of the saphenous nerve, which branches from the femoral nerve. Radiographic deterioration of a hip joint does not correlate with pain distribution or patient dysfunction as measured by the Oxford Hip Score.     

Does the fabella contribute to the reinforcement of the posterolateral corner of the knee by inducing the development of associated ligaments?

The fabellofibular (FF) and arcuate ligaments are closely colocated at the posterolateral corner of the knee. However, a bony fabella is often absent in Japanese subjects. We investigated these structures morphometrically using 212 knees. A thick FF ligament was found in 38.1% (40/105) of knees with a hard fabella. When identified histologically, a bony fabella accompanied a thick FF in 82.8% (24/29). Conversely, a thin or indefinite FF ligament and an elastic-textured fabella co-existed in 77.9% (60/70) of knees. There were no strong correlations between the morphology of the fabella and the arcuate ligament. Thus, a hard or bony fabella seemed to relate to thickening of the FF ligament. In contrast, the thicknesses of the FF and arcuate ligaments were negatively correlated. When the FF ligament was more than 5mm thick, indicating that it was as strong as the lateral collateral ligament, no arcuate ligament could be identified. Conversely, a thin or indefinite FF ligament often accompanied a well-developed arcuate ligament (61.9%, 96/155). Our observations suggest that these ligaments act in a complementary manner to stabilize the posterolateral corner. A possible common function is fixation of the popliteal tendon on the joint capsule and lateral meniscus, rather than direct stabilization against rotation stress.     

Operative technique to harvest an arterial flap from the posterolateral calf region: how can we elevate a lateral gastrocnemius perforating artery flap safely?

The posterior calf region is a useful donor site for skin or composite flaps including muscle and/or nerves. We reported the first clinical use of the lateral gastrocnemius perforating artery flap including a vascularized sural nerve in 2003. This flap was elevated based on a perforator arising from the lateral head of the gastrocnemius muscle. However, we have since encountered vascular variations in these perforators. We subsequently developed a reliable technique for harvesting this flap in the course of treating 10 patients. Safe flap elevation from the lateral aspect of the posterior calf requires preservation of one of the superficial sural arteries until reliable perforators arising from gastrocnemius muscle lateral head are encountered during dissection. When such perforators are not observed, nutrient vessels such as superficial sural arteries or muscle perforators originating from vessels other than the lateral sural artery must be selected as a flap pedicle.     

Secondary resurfacing of the patella after primary total knee arthroplasty does the anterior knee pain resolve?

Although it has been shown that the risk of anterior knee pain is greater in patients with nonresurfaced patellae, it is not exactly clear whether the pain would resolve with secondary resurfacing of the patella. Thirty-nine patients (41 knees) underwent secondary patellar resurfacing between January 2001 and January 2007. The mean age was 66 years. The mean body mass index was 29.2 kg/m². The average time from primary total knee arthroplasty to resurfacing procedure was 29 months. The mean follow-up was 54 months. Anterior knee pain was the indication for secondary resurfacing in all patients. Although the clinical and functional knee scores improved significantly for whole cohort, 8 patients (8 knees) were dissatisfied with the outcome of surgery. This study highlights that secondary resurfacing is not an always rewarding procedure and patients need to be consulted appropriately with regard to the outcome.     

Chronic prostatitis and sensory urgency: Whose pain is it?

Difficulties encountered in diagnosing and effectively treating chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is frustrating for clinicians and patients. Scientific evidence cannot establish an exact relationship between the prostate and the symptoms of CP/CPPS, and the prostate continues to be the diagnosis of convenience in this complex syndrome in men. However, if the pain is not the prostate’s, whose pain is it? A heterogeneous group of insults can result in a common neurogenic pain response, resulting in recurring pain and voiding or sexual dysfunction. To add to this dilemma, certain life-threatening diagnoses, such as carcinoma-in-situ, is in the differential diagnosis and must be excluded. Urodynamics may be useful in evaluating and treating patients whose voiding symptoms predominate. However, many patients with CP/ CPPS will not have measurable abnormalities by conventional methods and likely suffer from a functional somatic syndrome that is best treated with a multimodality approach.