Pathological fractures in the metaphysis of tibia are difficult to treat by conventional methods. We report a case of plasma cell tumour in the proximal tibia in a 71 year old patient treated successfully with a locking compression plate and chemotherapy.
A 71 year old patient presented initially with a history of confusion and agitation. Blood investigations revealed hypocalcaemia and acute renal failure. The Bence-Jones proteins were 2.9 gm / 24hours. Bone marrow aspiration was performed on two occasions, which did not confirm myeloma. The patient was commenced on melphalan and hydrocortisone therapy. At six weeks the patient’s symptoms and blood parameters improved. After four months patient presented with pain in the left tibia. Radiographs were performed which revealed a large lytic lesion in the upper third of the left tibia (Fig. 1) with a breach in the posterior cortex. The Mirrel’s score was 11 out of 123. As the lesion was likely to fracture if untreated, it was stabilised by an AO locking compression plate (Fig. 2) (Startec Medicals, UK ) The mini open technique was used. No radiotherapy was given to the lesion. The lesion in the proximal tibia showed further expansion during the initial follow up at three months. However, there were no signs of loosening of plate and screws. The patient received 6 cycles of melphalan and hydrocortisone therapy and was not weight bearing. Further radiographs at 15 months demonstrated consolidation in the lesion and patient was able to mobilise with two elbow crutches moving onto full weight bearing at 24 months follow-up (Fig 3).
Pathological juxta-articular lesions of the tibia pose a difficult problem for fixation. The intramedullary fixation is not suitable. The recent introduction of the LCP uses the indirect reduction technique and percutaneous fixation, there by achieving biological fixation. The key to this internal fixator is the locking mechanism of the screw in the implant, which provides angular stability. This ensures that compression forces on the bone surface are not necessary to gain stability of the bone-implant construct; this improves fracture healing and provides an excellent holding force even in osteoporotic bone4. In our case the plate was used percutaneously without opening the lesion. The LCP stabilised the proximal tibia for 15 months before the lesion healed and patient started weight bearing. The patient’s pain improved and the lesion healed without any complication. To the best of our knowledge, this is the first reported case of a plasma cell tumour in the proximal tibia, which has been successfully treated with the LCP.
Plasma cell tumor in proximal tibia.
From the provided proximal tibial X-ray images, the following findings are noted:
Considering the patient’s age (71 years), the pathological fracture of the proximal tibia, and the radiological manifestation of bone destruction, the potential or differential diagnoses include:
Based on the patient’s age, clinical symptoms, medical history, and intraoperative pathological examination results, the most likely diagnosis is solitary plasmacytoma of the proximal tibia (also referred to as plasmacytoma or a localized presentation associated with multiple myeloma). In this case, pathological findings and concurrent treatment (chemotherapy) confirm this likelihood.
If a complete pathological and serological workup (e.g., serum immunoglobulin tests, bone marrow aspiration, etc.) has not been conducted, further laboratory and imaging evaluations are necessary to determine whether the disease is multiple myeloma or solitary plasmacytoma.
Surgical treatment: In this case, a Locking Compression Plate (LCP) with percutaneous fixation was utilized to protect the periosteal blood supply and provide stable internal fixation, thereby supporting and stabilizing the pathological fracture site. Combined with postoperative chemotherapy (or radiotherapy, depending on the type and extent of the plasmacytoma), this approach can inhibit tumor cells and promote lesion healing.
Systemic treatment: Patients with plasmacytoma typically receive chemotherapy. If necessary, according to multiple myeloma treatment guidelines or a multidisciplinary orthopedic oncology approach, the use of targeted agents, immunomodulatory drugs, and bone-protective agents (such as bisphosphonates) may be considered to achieve a more comprehensive therapeutic effect.
After stable orthopedic fixation is achieved, a gradual approach to functional exercises should be employed:
Recommendations Based on the FITT-VP Principle:
If the patient has fragile bones or compromised cardiopulmonary function, exercise intensity should be advanced under the guidance of professional rehabilitation therapists and the supervising physician. Falls and excessive loading that might lead to refracture must be carefully avoided.
This report is a reference analysis based on the information currently available and should not replace an in-person consultation or professional medical advice. If you have any questions or if the condition changes, please seek medical attention promptly.
Plasma cell tumor in proximal tibia.
