Orthopaedic issues in the musculoskeletal care of adults with cerebral palsy

Authors


  • CONFLICTS OF INTEREST
    The authors declare no conflicts of interest.

Helen M Horstmann at Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA, USA. E-mail: Helen.Horstmann@uphs.upenn.edu

Abstract

Aims  Orthopaedic care of adults with cerebral palsy (CP) has not been well documented in orthopaedic literature. This paper focuses on some of the common problems which present themselves when adults with CP seek orthopaedic intervention. In particular, we review the most common orthopaedic issues which present to the Penn Neuro-Orthopaedics Program.

Method  A formal review of consecutive surgeries performed by the senior author on adults with CP was previously conducted. This paper focuses on the health delivery care for the adult with orthopaedic problems related to cerebral palsy. Ninety-two percent of these patients required lower extremity surgery. Forty percent had procedures performed on the upper extremities.

Results  The majority of problems seen in the Penn Neuro-Orthopaedics Program are associated with the residuals of childhood issues, particularly deformities associated with contractures. Patients are also referred for treatment of acquired musculoskeletal problems such as degenerative arthritis of the hip or knee. A combination of problems contribute most frequently to foot deformities and pain with weight-bearing, shoewear or both, most often due to equinovarus. The surgical correction of this is most often facilitated through a split anterior tibial tendon transfer. Posterior tibial transfers are rarely indicated. Residual equinus deformities contribute to a pes planus deformity. The split anterior tibial tendon transfer is usually combined with gastrocnemius-soleus recession and plantar release. Transfer of the flexor digitorum longus to the os calcis is done to augment the plantar flexor power. Rigid pes planus deformity is treated with a triple arthrodesis. Resolution of deformity allows for a good base for standing, improved ability to tolerate shoewear, and/or braces. Other recurrent or unresolved issues involve hip and knee contractures. Issues of lever arm dysfunction create problems with mechanical inefficiency. Upper extremity intervention is principally to correct contractures. Internal rotation and adductor tightness at the shoulder makes for difficult underarm hygiene and predispose a patient to a spiral fracture of the humerus. A tight flexor, pronation pattern is frequently noted through the elbow and forearm with further flexion contractures through the wrist and fingers. Lengthenings are more frequently performed than tendon transfers in the upper extremity. Arthrodesis of the wrist or on rare occasions of the metacarpal-phalangeal joints supplement the lengthenings when needed.

Conclusions  The Penn Neuro-Orthopaedics Program has successfully treated adults with both residual and acquired musculoskeletal deformities. These deformities become more critical when combined with degenerative changes, a relative increase in body mass, fatigue, and weakness associated with the aging process.

When the child with cerebral palsy (CP) becomes an adult, there are new medical and orthopaedic challenges. Gone are the childhood medical services with clinics geared to the growing child with CP. Instead, adult orthopaedic care tends to be fragmented and delivered by clinicians with expertise in general orthopaedics without a neuromuscular background or interest.1 This paper will focus on some of the most frequent orthopaedic surgical issues we see in our neuro-orthopaedic clinic for adults.

CP is defined to be a non-progressive disorder of movement and posture. Interpreting this in the light of present day science a convening group of international experts noted CP to include a ‘group of permanent disorders of the development of movement and posture, causing activity limitation, that are attributed to non-progressive disturbances that occurred in the developing fetal or infant brain.’2 Functional deterioration is noted in the aging adult with CP particularly those with abnormal movement patterns during ambulation.3 From Sweden, results of a questionnaire of 221 adults with CP showed 80% of adults with CP had contractures. 18% had pain every day. About 64% were able to walk but 35% of this group noted decreased walking ability.4

The prevalence of CP in the US is about two per 1000.5 There are an estimated 700 000 children and adults with CP in the United States.7 This compares with about 500 000 new cases of traumatic brain injury in the United States yearly. Further 99% of children with CP but without severe functional problems survive to adulthood. When there was severe functional disability, in ambulation, manual dexterity, and mental ability, 20-year survival was 50%.6

Purpose

The purpose of this paper is to discuss specifically the types of orthopaedic surgical intervention done on adults with CP. There are several world renowned pediatric orthopaedic centers in the metropolitan Philadelphia area including Children’s Hospital of Philadelphia, duPont Children’s Hospital, in Wilmington, Delaware, Shriner’s Hospital, and Saint Christopher’s Hospital for Children. All of these centers have pediatric orthopaedic surgeons who are experts in the management of the orthopaedic needs of the child with CP. As is typical in many pediatric centers in the United States, no orthopaedic treament is offered at these centers after the age of 18. The Penn Neuro-Orthopaedics Program has partnered with these regional pediatric centers to provide ongoing musculoskeletal care for their patients entering the adult health care system.

The Neuro-Orthopaedics Program at the University of Pennsylvania provides orthopaedic care for adults who have musculoskeletal problems as a consequence of neurological disorders. The Neuro-Orthopaedics Program also provides treatment of the general orthopaedic disorders which are acquired during adult life in neurological patients. The Neuro-Orthopaedics Program is a component of the Penn Comprehensive Neurosciences Center (CNC). The Penn CNC combines the resources of the departments of Neurology, Neurosurgery, Rehabilitation, Psychiatry, Orthopaedic Surgery, and Neurosciences Research. Adults with CP obtain coordinated services from the CNC as needed.

Materials and Methods

The most common deformities, the orthopaedic procedures and their indications, seen in our CP patient population are presented here. All patients presenting to our clinic were referred for ongoing adult care or possible orthopaedic surgical intervention for a specific problem. All surgeries were goal-oriented and were done to improve the quality of life for the patient and often the caregivers. These goals include: decreased energy expenditure associated with poor mechanics of ambulation, improved ambulation limited by deformities, decreased difficulties associated with activities of daily living by improving contractures, and decreased pain due to deformity or arthritis, and decreased difficulty with shoe wear or bracing. The preoperative planning included detailed history, review of past procedures, and extensive physical examination. In many cases the patients were sent for electrodynamic gait analysis if they were ambulatory or motion analysis in the case of the upper extremities. Specific questions were to be addressed in sending these patients for analysis: for instance, which muscles are spastic and the principle cause of the existing deformity. Specific surgical plans were formulated with due consideration of the findings of motion analysis.

Even when the patient was non-ambulatory, problems from deformity could hinder their abilities to sit comfortably, wear shoes comfortably, get perineal care with ease and comfort, and prevent decubitus ulcers. Problems, especially contractures and unstable, uncontrolled joints in the upper extremity could preclude joystick use, assistive use of a non-functional limb, and/or hygiene care. All of the patients were operated upon by the senior author (MAK). The patients were followed at regular intervals postoperatively (2, 6, 12, and 24 wks postoperatively) for wound management, deformity management, bracing, and therapy needs. Typically after 1 year, unless specific needs arose, further follow-up was done by the patient’s primary care physician with oversight by a physical medicine and rehabilitation specialist.

Results: Surgeries About the Lower Extremity in Adults with CP

Foot and ankle

In our neuro-orthopaedic clinic over a 5-year span, 105 patients with CP underwent 508 surgeries through the lower extremities. About 41% of these surgeries (209 of 508 procedures) were done to correct foot and ankle deformities.8

These deformities made shoe wear difficult, caused pain and hindered walking. Flexible and dynamic deformities are addressed with tendon lengthenings and transfers (Fig. 1). The most frequent problem addressed was equinus. Correction of an equinus deformity required lengthening of the Achilles tendon or the gastroc soleus in 58 of the 105 patients who underwent lower extremity surgery. Dynamic electromyography studies gait studies help tailor the specific plan to allow appropriate postoperative muscle balance (Fig. 2). When an equinus deformity was flexible, intramuscular lengthening of the gastrocnemius and soleus muscles or tendoachilles lengthening (TAL) was performed. To further augment the calf strength the flexor digitorum longus (FDL) was transferred to the medial os calcis and anchored with an interference screw.9 A split anterior tibialis transfer balances the dorsiflexion forces even when the muscle is spastic. At the same surgical sitting, the extensor hallucis longus (EHL) was usually transferred to the medial cuneiform and secured with an interference screw to augment dorsiflexion strength. Additionally, a plantar release was frequently required. The posterior tibialis is lengthened if there is a varus deformity and no tendency toward valgus in midstance of the gait cycle (Fig. 3). Lengthening of the posterior tibialis comprised only 8% (18 of 209) of all foot procedures.8 When deformities are fixed and capsular and soft tissue releases are insufficient for correction and stabilization, arthrodesis is indicated (Fig. 4). Additional procedures included arthrodesis of the hindfoot with triple arthrodesis to correct boney hindfoot deformities, arthrodesis of the first metatarsal phalangeal joint for hallux valgus or dorsal bunions and arthrodesis of the interphalangeus for valgus or flexion deformity of the great toe.10

Figure 1.

 Typical flexible spastic equinovarus foot. This is corrected with a split anterior tibialis transfer, transfer of the FDL to the os calcis medially, EHL transfer to the medial cuneiform, plantar release, gastroc soleus lengthening, and posterior tibial lengthening.

Figure 2.

 Electromyography gait studies showing spastic anterior tibialis and posterior tibialis in dynamic equinovarus (courtesy of Alberto Esquenazi MD, Moss Rehabilitation).

Figure 3.

 Medial intraoperative wounds for dynamic equinovarus correction.

Figure 4.

 Fixed equinovarus deformities precluding shoewear or standing and requiring transfers and bone realignment.

Knee

Knee flexion contractures continue to be problematic in adulthood. The most common problem is knee flexion contracture with knee pain associated with chondromalacia and patella alta. Hamstring lengthenings needed to be supplemented with posterior knee capsular releases in 32% of our hamstring cases.8 This afforded some relief of symptomotology, a more upright position for standing and walking and a more efficient gait pattern. No changes were noted regarding the position of patella alta when present. Femoral rotational osteotomies to correct lever arm dysfunction and internal femoral rotation from uncorrected childhood deformities were done in 8% of patients. A large number of the patients seen in our offices had previous derotation osteotomies in childhood, 32 of 105 patients.8 These were not the same patients who had these surgeries later in life under our care. Postoperative recovery to regain strength was longer in adults than with children with similar procedures.

Hip

Thirty-four percent of lower extremity procedures were performed to correct hip deformities. Hip contracture releases were also a common procedure. Most frequently this involved the adductors often in combination with the hip flexors (iliopsoas). One in eight (12 of 105) of our operative group of patients who had lower extemity surgery required Girdlestone procedures with resection of the proximal femur because of intractable pain about the hip associated with degenerative changes due to hip dysplasia and/or dislocation.8Girdlestone procedures were done only in the non-ambulatory group. When total hip replacement was done, all other lower extremity deformities were corrected in advance of the arthroplasty. It is important to remove all abnormal mechanical forces of the hip before or at the time of the arthroplasty to ensure longevity of the procedure. This especially applies to spastic hip adductors. Overall, ninety-two percent of our adult CP patients underwent lower extremity surgery. All patients who were ambulatory before surgery, improved their ambulation status postoperatively. Those patients who were not ambulatory had correction of their contractures, relief of pain, improved positioning, and ease of care.

Surgeries About the Upper Extremity

The most common pattern of deformities in the adult is similar to their pediatric counterparts. This includes tight adduction and internal rotation of the shoulders, elbow flexion, pronated forearm, tight wrist flexors, tight finger flexors, and thumb in palm deformities (Fig. 5). Typically, patients referred to our offices had had fewer upper extremity surgical procedures as children than they had to the lower extremity (16 upper extremity procedures vs 369 lower extremity cases). One-half (57 of 114) of our adult CP patients underwent upper extremity surgery. These 57 patients had 144 upper extremity surgical procedures. The most common procedures (42%) were done to correct wrist and hand deformities. Shoulder adduction, internal rotation contractures (30% of procedures), and elbow flexion contractures (30% of procedures) were also seen frequently and required surgical treatment. Internal rotation contractures of the shoulder predispose to spiral fractures of the humerus and should be corrected when possible. The vast majority of procedures in the upper extremity were tendon lengthenings and soft tissue releases. Only 10% of all upper extremity procedures involved arthrodesis.

Figure 5.

 Contracted upper extremity deformity in an adult with cerebral palsy needing surgery.

Shoulder

Adduction, internal rotation contractures of the shoulder cause difficulty with underarm hygiene and donning clothes. To address this, shoulder releases are done through a deltopectoral incision which allows access to the contracted muscles. The pectoralis major, latissimus dorsi, and teres major muscle are released from their insertion in the proximal humerus, particularly in the non-functional upper arm. When there is more function and less contracture or spasticity, these muscles were fractionally lengthened instead. The short head of the biceps is fractionally lengthened if needed. Two of our patients required shoulder arthroplasty. Preoperative chemodenervation of shoulder muscles with overactivity is strongly advised. Concomitant tendon lengthenings and aggressive postoperative management of pain and spasticity are needed to maintain the stability of the shoulder during the perioperative period.

Elbow, forearm, and hand

Elbow flexion contracture releases are done through a lateral incision at the elbow. Sequentially, the brachioradialis, the distal biceps tendon and lacertus fibrosus, and the distal brachialis are fractionally lengthened over the muscle bellies or released at their insertions. Forearm pronation can be caused by the pronator teres or pronator quadratus. These are lengthened or released through volar forearm incisions. Decisions regarding flexor – pronator lengthenings are based on electromyographic information gleaned from motion studies of the upper extremity in a motion analysis laboratory.

Wrist and finger flexion problems are also addressed through volar forearm surgical intervention. A fixed wrist contracture limits use of the hand. Finger flexors contribute to a wrist flexion deformity. Severe fixed flexion causes median nerve compression. Finger extensors are typically weak. Patients often have volitional control of their finger flexorswhich can be unmasked with flexor lengthenings. We note that there is often better control of the flexor digitorum profundus than the flexor digitorum superficialis. Through a long volar incision from the wrist to the proximal forearm, sequential releases are done of the pronator teres, the palmaris longus, the flexor carpi radialis, and flexor carpi ulnaris. When the arm has no function and there is significant finger contracture, a transfer of the flexor digitorum superficialis to the flexor digitorum profundus to effectively lengthen the flexors allows maximum extension of the fingers.11 The tendon of the flexor pollicis longus additionally is transferred to the profundus with the thumb held in maximum extension in non-functional hands. Alternatively, when there is selective hand function, tendons are selectively lengthened based on electromyography motion analysis studies coupled with physical examination. Tendon transfers are protected in splints for 6 weeks postoperatively. Otherwise active hand motion is begun a week after surgery. Intrinsic plus deformities with flexion at the metacarpal phalangeal joint is caused by overactive intrinsic muscles. Myotendinous lengthening of the palmar interossei allows correction of intrinsic minus deformities. The thumb adductors were lengthened in functional hands with a Matev slide.12 To prevent further tendencies of thumb-in-palm deformity, the recurrent motor branch of the median nerve is transected at the base of the thumb in severe cases. Similarly the motor branches but not the sensory branch of the ulnar nerve are transected through Guyon’s Canal. If needed a wrist fusion is done through a dorsal incision. In our patients a fusion was done in 12 of 57 patients who underwent upper extremity surgery.

Discussion

Some problems associated with lack of the weight bearing of walking and the lack of loading exercise such as osteopenia and osteoporosis,13–15 did not present themselves to our clinic. We believe this is because we serve primarily as a tertiary referral center specializing in long term orthopaedic problems rather than as a general needs orthopaedic office for acute problems. We assume these problems are generally addressed by other clinicians especially internists. In the case of the University of Pennsylvania, this peripheral and related care occurs through the Penn Comprehensive Neurosciences Center of which our Neuro-Orthopaedics Program is a part. We note the lack of adult orthopaedic surgeons with an interest or background in addressing the neuro-orthopaedic concerns of the adult with CP. In the University of Pennsylvania Orthopaedics Program these are addressed by surgeons whose background and orthopaedic training started in pediatric orthopaedics (HMH, HH) or by our senior surgeon with fellowship training and clinical practice in adult neuroorthopaedic care (MAK). We feel more of these issues could be addressed by surgeons crossing the lines of their hospital age limits to focus on problems of the patient with CP presenting as adults. Particularly, as there are more pediatric orthopaedic surgeons trained with these interests, working in the adult surgical arena for these special needs patients on occasion can meet the needs of the adult with CP.

It is generally understood that the adult with CP and other neuro-orthopaedic problems can benefit from a consistent exercise program to improve their cardiopulmonary health, build strength and endurance, as well as mobilize their endorphins for feelings of general well-being.16 We feel that with limbs in more functional positions more activities can be pursued with less effort. Strength has been shown in children to be a better determinant of function than the amount of spasticity in ambulators.17 Our studies have not evaluated specific change in strength but rather we have looked at ambulatory levels as a determinant of outcome effectiveness and improvement of position when non-ambulatory.

Conclusions

The Penn Neuro-Orthopaedics Program has successfully treated adults with CP with both residual and acquired musculoskeletal deformities. These deformities become more critical when combined with degenerative changes, a relative increase in body mass, fatigue and weakness associated with the aging process. A comprehensive management plan that includes the involvement of other specialties ensures a successful outcome. Collaborative efforts for continuity of care for adults with CP in our clinic model address these needs.

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