Staged Bi-compartmental Knee Arthroplasty for Contralateral Compartment Failure After Medial Unicompartmental Knee Arthroplasty in Dialysis Patients: Two Case Reports.

Unicompartmental knee arthroplasty (UKA) is a minimally invasive surgical technique with good clinical outcomes; however, its outcomes in patients undergoing hemodialysis are unknown. Herein, we report two cases of patients undergoing hemodialysis who underwent staged bi-compartmental UKA (Bi-UKA) for early contralateral compartment failure after medial UKA. We describe the case of early contralateral compartment failure after medial UKA in two women patients aged 71 and 72 years with a dialysis history of seven and 22 years, respectively. Three months after right medial UKA, she had persistent joint edema and arthralgia after minor trauma, with recurrent gait disturbance in the first case. An MRI showed a bone marrow lesion in the contralateral compartment, and a lateral UKA was added. In the second case, the knee pain worsened without any trigger three years after leaving the medial UKA. A subchondral insufficiency fracture (SIF) was diagnosed by a plain radiograph showing a radiolucent area on the lateral femoral condyle. Gait disturbance did not improve, and a lateral UKA was performed. In our hospital, medial UKA was performed on seven knees of dialysis patients in 10 years since 2011, and contralateral compartment failure was observed in two knees at an early stage. In both cases, lumbar bone density was normal and there was no postoperative overcorrection in leg alignment, but a SIF of the contralateral side occurred, suggesting that bone fragility of the contralateral compartment due to long-term dialysis was the underlying cause. Staged Bi-UKA was minimally invasive and useful as a revision surgery.

The clinical results of bi-cruciate vs posterior stabilized total knee arthroplasty for flexion contracture in osteoarthritic knee.

BACKGROUND: The improvement of flexion contracture is important in knee arthroplasty since residual flexion contracture postoperatively is associated with decreased quality of life and patient satisfaction. In this study, we investigated the effect of bi-cruciate stabilized (BCS)-type total knee arthroplasty (TKA) as compared to posterior stabilized (PS)-type TKA on osteoarthritic primary knees with flexion contractures. METHODS: 59 TKAs from January 2014 to December 2020, of which 30 were PS-type TKAs (NexGen LPS-flexⓇ; 76.3 years, BMI 27.5) and 29 BCS-type TKAs (Journey IIⓇ; 72.5 years, BMI 28.6), were performed for knee osteoarthritis with preoperative flexion contracture of 15° or greater. Full extension was obtained intraoperatively during all TKAs. Clinical outcomes, radiological evaluations, and the amount of additional distal femoral osteotomy during TKA were evaluated in a retrospective study design. RESULTS: The range of motion improved in the both groups. Postoperative flexion contracture was significantly improved in the BCS group. Knee Society Score improved significantly in both groups, with no difference between the two groups. The amount of additional distal femoral osteotomy was 2.5 ± 1.3 mm for the PS group, and 1.8 ± 1.5 mm for the BCS group, showing a significant difference (p = 0.04). DISCUSSION: The BCS-type TKA significantly improved preoperative flexion contracture and reduced the amount of additional distal femoral osteotomy compared to PS-type TKA. This is attributed to the anterior cam in the BCS-type TKA, which leads to a smaller amount of protrusion of the posterior femoral condyle from the posterior margin of the tibial component in the BCS-type in knee extension, as compared to the PS-type.

[Sudden-onset monoplegia of the upper limb due to traumatic subclavian artery pseudoaneurysm after an interval of three days from tumbling].

A 66-year-old woman was admitted to our institution with sudden-onset weakness of her left upper limb. Neurological examination revealed monoplegia and sensory loss of the limb. A brain MRI did not find evidence of an acute ischemic stroke. Her medical history revealed that she had fallen and bruised her shoulder 3 days earlier. Detailed physiological examination revealed that there was a mild subcutaneous ecchymosis with tenderness in the left shoulder. An additional contrast-enhanced chest CT scan showed a fracture of the clavicle diaphysis and a pooling contrast agent demonstrating a 60*40 mm mass near the left subclavian artery (SUB-A) which suggested a pseudoaneurysm. We determined that her symptoms were due to compression of the brachial plexus by immediate growth of a traumatic SUB-A pseudoaneurysm (TSAP) due to her earlier fall. For reduction of pressure to the brachial plexus by the TSAP and prevention of rupture, an endovascular treatment team performed endovascular internal trapping of the left SUB-A just distal to the orifice of the left vertebral artery and a cardiovascular surgeon performed percutaneous drainage of the pseudoaneurysm. After the procedure, the palsy and sensory loss of the left hand gradually improved. A TSAP could be one of the causes of sudden-onset palsy of the upper limb within a few days after a fall.

Differences in patellofemoral alignment as a result of patellar shape in cruciate-retaining total knee arthroplasty without patellar resurfacing at a minimum three-year follow-up.

BACKGROUND: Although the patellofemoral (PF) joint shape of the femoral implant in a particular prosthetic design is identical, the articular surface shape of the patella varies between individuals. The present study investigated the effects of patellar shape on the postoperative PF joint in a cruciate-retaining total knee arthroplasty (CR-TKA) without patellar resurfacing and with at least three years of follow-up. METHODS: This study investigated 76 knees of 62 patients who underwent CR-TKA without patellar resurfacing for varus osteoarthritis. Shape of the patella was classified in terms of the patellar facet angle (angle formed by the medial and lateral articular surfaces) as measured on axial plain X-ray. Subjects were divided into Group A with patellar facet angle ≤126° (34 knees) and Group B with patellar facet angle >126° (42 knees). RESULTS: Anterior knee pain (AKP) was evident in four knees in Group A and one knee in Group B. Postoperative lateral patellar tilt angle was significantly larger in Group A than in Group B. Progression of osteosclerosis in the patella was present in 12 knees in Group A and three knees in Group B. CONCLUSION: This study found that for a patella with a small patellar facet angle, lateral tilt of the patella was significantly increased after TKA, and a high rate of osteosclerosis was evident at >3years after operation. Performing TKA without patellar resurfacing on a patella with a small patellar facet angle may entail a higher risk of postoperative AKP; pre-operative evaluation of the shape of the patella is therefore important.

Assessing coronal laxity in extension and flexion at a minimum of 10 years after primary total knee arthroplasty.

PURPOSE: Favourable long-term results after total knee arthroplasty (TKA) require appropriate soft tissue balance. However, the relationships between long-term results after TKA surgery and mediolateral laxities at extension and at 90° flexion remain unknown. This study therefore quantitatively assessed ligament balance at extension and at 90° knee flexion at least 10 years after primary TKA, as well as clarifying the relationships between long-term outcomes and mediolateral laxities. METHODS: This study included 49 knees (19 CR type and 30 PS type) of 33 patients followed up for at least 10 years after TKA at our hospital. Plain radiographs were obtained with about 150 N of varus or valgus stress using a Telos arthrometer at extension. At 90° flexion, epicondylar views were obtained under a 1.5-kg load and with about 10 kg of varus or valgus stress. RESULTS: Lateral laxity of about 5° was observed in both extension and flexion, with total laxities of varus and valgus stress each less than 10°. Postoperative clinical outcomes were good, with significant improvements in extension angle, femorotibial angle, and KSS, and no loosening in any knee. CONCLUSIONS: Good long-term results of TKA can be obtained with a lateral laxity of about 5°, equivalent to that of healthy knees. LEVEL OF EVIDENCE: III.

Functional cortical deafferentation from the subcortical structures in a patient with early myoclonic encephalopathy: a functional neuroimaging study.

We, for the first time, used functional neuroimaging analyses for a girl with early myoclonic encephalopathy (EME). The interictal single photon emission computed tomography (SPECT) and [18F]-fluoro-D-deoxyglucose positron emission tomography (FDG-PET) at 1 month of age showed hypoperfusion and hypometabolism of bilateral basal ganglia, thalami, and the right parietooccipital cerebral cortices, showing that there is profound dysfunction of the basal ganglia and thalamus as well as cerebral cortex. On the other hand, subtraction ictal SPECT of tonic spasms clearly showed hyperperfusion of the bilateral basal ganglia, thalami, brainstem, and deep cortical layer of bilateral frontoparietal cortices. The present study suggests that functional deafferentation of the cortex from subcortical structures exists in EME, and that these imaging abnormalities may provide insight into the pathophysiology of suppression-burst pattern in EME.

Successful treatment of a 2-year-old girl with intractable myasthenia gravis using tacrolimus.

We used tacrolimus to successfully treat a patient with childhood-onset oropharyngeal myasthenia gravis (MG). A girl (2 years, 5 months old) with oropharyngeal MG responded partially to treatment including pyridostigmine bromide, intravenous immunoglobulin, and prednisolone (2 mg/kg/day) for 7 weeks, but this resulted in worsening of her eye symptoms. By contrast, tacrolimus at 2 mg/day resulted in complete remission of the MG, which made it possible to reduce the dose of prednisolone. This is a rare report of the use of tacrolimus as an effective treatment for patients with intractable childhood-onset MG.